Publications by authors named "Liona C Poon"

55 Publications

Prediction of spontaneous preterm birth by cervical length in the first trimester of pregnancy: Comparison of two measurement methods.

Acta Obstet Gynecol Scand 2021 Mar 8. Epub 2021 Mar 8.

Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, Hong Kong.

Introduction: Our objectives were to compare the single-line and two-line methods of cervical length measurement in the first trimester of pregnancy and to evaluate the potential value of the first trimester cervical length measured by the two methods in predicting spontaneous preterm birth.

Material And Methods: This was a prospective study in singleton pregnancies at 11+0 to 13+6 weeks of gestation. Cervical length was measured by two methods: (i) a linear distance between the two ends of the glandular area around the endocervical canal (single-line method) and (ii) a sum of a linear distance from the internal os to the greatest cervical curvature and a linear distance from this point of the cervix to the external os (two-line method). The screening performance of the first trimester cervical length measured by the two different methods for the prediction of spontaneous preterm delivery was assessed by receiver-operating characteristics (ROC) curve analysis. The areas under the ROC (AUROC) were compared by De Long test.

Results: A total of 1484 consecutive singleton pregnancies were included in this study. Spontaneous preterm delivery at <37 and <32 weeks occurred in 75 cases (5.1%) and 12 cases (0.8%), respectively. The median cervical length measured by the single-line method was significantly shorter than that by the two-line method (33.5 vs 36.5 mm, p < .001). Compared with the term delivery group, the median cervical length measured by the two-line method was shorter in women with spontaneous delivery at <32 weeks of gestation (36.5 vs 33.6 mm, p < .01). No significant difference in the median cervical length measured by the single-line method was detected between the spontaneous preterm delivery and term delivery groups. Receiver-operating-characteristic curves demonstrated that cervical length measured by the two-line method achieved better performance in predicting spontaneous delivery at <32 weeks compared with the single-line method (AUROC: 0.72 vs 0.61, p < .01).

Conclusions: We have demonstrated that the first trimester cervical length, measured by the two-line approach, holds promise as a potential screening tool for early spontaneous preterm delivery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/aogs.14138DOI Listing
March 2021

Genome-wide detection of cytosine methylation by single molecule real-time sequencing.

Proc Natl Acad Sci U S A 2021 Feb;118(5)

Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region, China;

5-Methylcytosine (5mC) is an important type of epigenetic modification. Bisulfite sequencing (BS-seq) has limitations, such as severe DNA degradation. Using single molecule real-time sequencing, we developed a methodology to directly examine 5mC. This approach holistically examined kinetic signals of a DNA polymerase (including interpulse duration and pulse width) and sequence context for every nucleotide within a measurement window, termed the holistic kinetic (HK) model. The measurement window of each analyzed double-stranded DNA molecule comprised 21 nucleotides with a cytosine in a CpG site in the center. We used amplified DNA (unmethylated) and M.SssI-treated DNA (methylated) (M.SssI being a CpG methyltransferase) to train a convolutional neural network. The area under the curve for differentiating methylation states using such samples was up to 0.97. The sensitivity and specificity for genome-wide 5mC detection at single-base resolution reached 90% and 94%, respectively. The HK model was then tested on human-mouse hybrid fragments in which each member of the hybrid had a different methylation status. The model was also tested on human genomic DNA molecules extracted from various biological samples, such as buffy coat, placental, and tumoral tissues. The overall methylation levels deduced by the HK model were well correlated with those by BS-seq ( = 0.99; < 0.0001) and allowed the measurement of allele-specific methylation patterns in imprinted genes. Taken together, this methodology has provided a system for simultaneous genome-wide genetic and epigenetic analyses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.2019768118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7865158PMC
February 2021

Accuracy of the FMF Bayes theorem-based model for predicting preeclampsia at 11-13 weeks of gestation in a Japanese population.

Hypertens Res 2020 Nov 6. Epub 2020 Nov 6.

Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China.

This study aimed to investigate the diagnostic accuracy of the Fetal Medicine Foundation (FMF) Bayes theorem-based model for the prediction of preeclampsia (PE) at 11-13 weeks of gestation in the Japanese population. In this prospective cohort study, we invited 2655 Japanese women with singleton pregnancies at 11-13 weeks of gestation to participate, of whom 1036 women provided written consent. Finally, we included 913 women for whom all measurements and perinatal outcomes were available. Data on maternal characteristics and medical history were recorded. Mean arterial pressure (MAP), uterine artery pulsatility index, and maternal serum placental growth factor (PlGF) were measured. The patients delivered their babies at Showa University Hospital between June 2017 and December 2019. Participants were classified into high- and low-risk groups according to the FMF Bayes theorem-based model. Frequencies of PE were compared between groups. The screening performance of the model was validated using the area under receiver operating characteristic (AUROC) curve. A total of 26 patients (2.8%) developed PE, including 11 patients (1.2%) with preterm PE (delivery at <37 weeks). The frequency of preterm PE was significantly higher in the high-risk group than in the low-risk group (3.8% vs. 0.2%, p < 0.05). This population model achieved a 91% detection rate for the prediction of preterm PE at a screen-positive rate of 10% by a combination of maternal characteristics, MAP, and PlGF. The AUROC curve for the prediction of preterm PE was 0.962 (0.927-0.981). In conclusion, the prediction of preterm PE using the FMF Bayes theorem-based model is feasible in the Japanese population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41440-020-00571-4DOI Listing
November 2020

Comparison of uterine artery Doppler measurements at 6 weeks of pregnancy after IVF between pregnancies that resulted in miscarriage and ongoing pregnancies.

Int J Gynaecol Obstet 2021 Feb 30;152(2):249-255. Epub 2020 Sep 30.

Department of Obstetrics and Gynecology, Assisted Reproductive Technology Unit, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.

Objective: To compare uterine artery pulsatility index (UTPI) at 6 weeks of pregnancy following in vitro fertilization (IVF) and embryo transfer (ET) between clinical pregnancies that resulted in a miscarriage and those that were ongoing beyond 12 weeks.

Methods: A prospective observational study was conducted in an IVF unit at Prince of Wales Hospital, Hong Kong, between December 1, 2017 and December 31, 2019. UTPI was measured at 6 weeks of pregnancy among women who conceived following IVF/ET.

Results: Among 153 participants, 22 (14.4%) had a miscarriage whereas 131 (85.6%) had an ongoing pregnancy beyond 12 weeks. Median UTPI in pregnancies that ended in a miscarriage was significantly lower than those that progressed beyond 12 weeks (2.1, IQR 1.9-2.4 vs 2.50, IQR 2.2-2.9, respectively; P<0.001). The likelihood of the pregnancy ending in a miscarriage when the UTPI was above the 75th percentile (>2.9), between the 25th-75th percentiles (2.2-2.9), and below the 25th percentile (<2.2) was 0%, 13.2%, and 27.7%, respectively (P=0.001).

Conclusions: IVF pregnancies that resulted in a miscarriage were associated with reduced resistance to uterine artery blood flow at 6 weeks of pregnancy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ijgo.13371DOI Listing
February 2021

Bradycardia-to-delivery interval and fetal outcomes in umbilical cord prolapse.

Acta Obstet Gynecol Scand 2021 01 14;100(1):170-177. Epub 2020 Sep 14.

Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, Hong Kong.

Introduction: Umbilical cord prolapse is a major obstetric emergency associated with significant perinatal complications. However, there is no consensus on the optimal decision-to-delivery interval, as many previous studies have shown poor correlation between the interval and umbilical cord arterial blood gas or perinatal outcomes. We aim to investigate whether bradycardia-to-delivery or decision-to-delivery interval was related to poor cord arterial pH or adverse perinatal outcome in umbilical cord prolapse.

Material And Methods: This was a retrospective study conducted at a university tertiary obstetric unit in Hong Kong. All women with singleton pregnancy complicated by cord prolapse during labor between 1995 and 2018 were included. Women were categorized into three groups. Group 1: persistent bradycardia; Group 2: any type of decelerations without bradycardia; and Group 3: normal fetal heart rate. The main outcome was cord arterial blood gas results of the newborns in different groups. Maternal demographic data and perinatal outcomes were reviewed. Correlation analysis between cord arterial blood gas result and time intervals including bradycardia-to-delivery, deceleration-to-delivery, and decision-to-delivery were performed for the different groups with Spearman test.

Results: There were 34, 30, and 50 women in Groups 1, 2, and 3, respectively. Cord arterial pH and base excess did not correlate with decision-to-delivery interval in any of the groups, but they were inversely correlated with bradycardia-to-delivery interval in Group 1 (Spearman's ρ = -.349; P = .043 and Spearman's ρ = -.558; P = .001, respectively). The cord arterial pH drops at 0.009 per minute with bradycardia-to-delivery interval in Group 1 (95% CI 0.0180-0.0003). The risk of significant acidosis (pH < 7) was 80% when bradycardia-to-delivery interval was >20 minutes, and 17.2% when the interval was <20 minutes.

Conclusions: There is significant correlation between bradycardia-to-delivery interval and cord arterial pH in umbilical cord prolapse with fetal bradycardia but not in cases with decelerations or normal heart rate. The drop of cord arterial pH is rapid and urgent delivery is essential in such situations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/aogs.13985DOI Listing
January 2021

Prevention of preeclampsia with aspirin.

Am J Obstet Gynecol 2020 Aug 21. Epub 2020 Aug 21.

Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Shatin, the Hong Kong Special Administrative Region of the People's Republic of China. Electronic address:

Preeclampsia is defined as hypertension arising after 20 weeks of gestational age with proteinuria or other signs of end-organ damage and is an important cause of maternal and perinatal morbidity and mortality, particularly when of early onset. Although a significant amount of research has been dedicated in identifying preventive measures for preeclampsia, the incidence of the condition has been relatively unchanged in the last decades. This could be attributed to the fact that the underlying pathophysiology of preeclampsia is not entirely understood. There is increasing evidence suggesting that suboptimal trophoblastic invasion leads to an imbalance of angiogenic and antiangiogenic proteins, ultimately causing widespread inflammation and endothelial damage, increased platelet aggregation, and thrombotic events with placental infarcts. Aspirin at doses below 300 mg selectively and irreversibly inactivates the cyclooxygenase-1 enzyme, suppressing the production of prostaglandins and thromboxane and inhibiting inflammation and platelet aggregation. Such an effect has led to the hypothesis that aspirin could be useful for preventing preeclampsia. The first possible link between the use of aspirin and the prevention of preeclampsia was suggested by a case report published in 1978, followed by the first randomized controlled trial published in 1985. Since then, numerous randomized trials have been published, reporting the safety of the use of aspirin in pregnancy and the inconsistent effects of aspirin on the rates of preeclampsia. These inconsistencies, however, can be largely explained by a high degree of heterogeneity regarding the selection of trial participants, baseline risk of the included women, dosage of aspirin, gestational age of prophylaxis initiation, and preeclampsia definition. An individual patient data meta-analysis has indicated a modest 10% reduction in preeclampsia rates with the use of aspirin, but later meta-analyses of aggregate data have revealed a dose-response effect of aspirin on preeclampsia rates, which is maximized when the medication is initiated before 16 weeks of gestational age. Recently, the Aspirin for Evidence-Based Preeclampsia Prevention trial has revealed that aspirin at a daily dosage of 150 mg, initiated before 16 weeks of gestational age, and given at night to a high-risk population, identified by a combined first trimester screening test, reduces the incidence of preterm preeclampsia by 62%. A secondary analysis of the Aspirin for Evidence-Based Preeclampsia Prevention trial data also indicated a reduction in the length of stay in the neonatal intensive care unit by 68% compared with placebo, mainly because of a reduction in births before 32 weeks of gestational age with preeclampsia. The beneficial effect of aspirin has been found to be similar in subgroups according to different maternal characteristics, except for the presence of chronic hypertension, where no beneficial effect is evident. In addition, the effect size of aspirin has been found to be more pronounced in women with good compliance to treatment. In general, randomized trials are underpowered to investigate the treatment effect of aspirin on the rates of other placental-associated adverse outcomes such as fetal growth restriction and stillbirth. This article summarizes the evidence around aspirin for the prevention of preeclampsia and its complications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2020.08.045DOI Listing
August 2020

Detection and characterization of jagged ends of double-stranded DNA in plasma.

Genome Res 2020 08 14;30(8):1144-1153. Epub 2020 Aug 14.

Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.

Cell-free DNA in plasma has been used for noninvasive prenatal testing and cancer liquid biopsy. The physical properties of cell-free DNA fragments in plasma, such as fragment sizes and ends, have attracted much recent interest, leading to the emerging field of cell-free DNA fragmentomics. However, one aspect of plasma DNA fragmentomics as to whether double-stranded plasma molecules might carry single-stranded ends, termed a jagged end in this study, remains underexplored. We have developed two approaches for investigating the presence of jagged ends in a plasma DNA pool. These approaches utilized DNA end repair to introduce differential methylation signals between the original sequence and the jagged ends, depending on whether unmethylated or methylated cytosines were used in the DNA end-repair procedure. The majority of plasma DNA molecules (87.8%) were found to bear jagged ends. The jaggedness varied according to plasma DNA fragment sizes and appeared to be in association with nucleosomal patterns. In the plasma of pregnant women, the jaggedness of fetal DNA molecules was higher than that of the maternal counterparts. The jaggedness of plasma DNA correlated with the fetal DNA fraction. Similarly, in the plasma of cancer patients, tumor-derived DNA molecules in patients with hepatocellular carcinoma showed an elevated jaggedness compared with nontumoral DNA. In mouse models, knocking out of the gene reduced jaggedness, whereas knocking out of the gene enhanced jaggedness. Hence, plasma DNA jagged ends represent an intrinsic property of plasma DNA and provide a link between nuclease activities and the fragmentation of plasma DNA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1101/gr.261396.120DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7462074PMC
August 2020

Risk factors for anxiety and depression among pregnant women during the COVID-19 pandemic: A web-based cross-sectional survey.

Medicine (Baltimore) 2020 Jul;99(30):e21279

Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR.

Introduction: The article presents a protocol of a cross-sectional study of mental health of pregnant women in relation to the coronavirus disease 19 (COVID-19) pandemic. The primary aim is to compare differences in anxiety and depression scores of pregnant women between countries affected by the COVID-19 pandemic. The secondary aim is to assess demographic, economic, and social aspects affecting maternal anxiety and depression scores among pregnant women worldwide in the time of the COVID-19 pandemic. Finally, we will be able to compare differences in perception of the different aspects of the COVID-19 pandemic (social distancing, restrictions related to delivery) between countries and according to the epidemic status (number of infected patients, number of reported deaths). The comparisons will also be done according to the COVID-19 status of the participants.

Methods And Analysis: It is a web-based anonymous survey of pregnant women living in countries affected by the COVID-19 pandemic. The survey is comprised of 3 sections:Web-based recruitment for health research has proven to be cost-effective and efficient. At current times with the COVID-19 pandemic, limited resources and social distancing restrictions, performing a mental health study involving pregnant women on a large international scale cannot be safely conducted without involving social-media.The fears of pregnant women fall into 3 categories: the medical condition, the economic status and the organization of daily activity.The study has received approval of the medical ethics committee and has been registered on Clinicaltrials.gov. Results will be published in peer-reviewed journals and made public through all available media.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MD.0000000000021279DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7387043PMC
July 2020

First trimester preeclampsia screening and prediction.

Am J Obstet Gynecol 2020 Jul 16. Epub 2020 Jul 16.

Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong Special Administrative Region, China. Electronic address:

Preeclampsia is a major cause of maternal and perinatal morbidity and mortality. Early-onset disease requiring preterm delivery is associated with a higher risk of complications in both mothers and babies. Evidence suggests that the administration of low-dose aspirin initiated before 16 weeks' gestation significantly reduces the rate of preterm preeclampsia. Therefore, it is important to identify pregnant women at risk of developing preeclampsia during the first trimester of pregnancy, thus allowing timely therapeutic intervention. Several professional organizations such as the American College of Obstetricians and Gynecologists (ACOG) and National Institute for Health and Care Excellence (NICE) have proposed screening for preeclampsia based on maternal risk factors. The approach recommended by ACOG and NICE essentially treats each risk factor as a separate screening test with additive detection rate and screen-positive rate. Evidence has shown that preeclampsia screening based on the NICE and ACOG approach has suboptimal performance, as the NICE recommendation only achieves detection rates of 41% and 34%, with a 10% false-positive rate, for preterm and term preeclampsia, respectively. Screening based on the 2013 ACOG recommendation can only achieve detection rates of 5% and 2% for preterm and term preeclampsia, respectively, with a 0.2% false-positive rate. Various first trimester prediction models have been developed. Most of them have not undergone or failed external validation. However, it is worthy of note that the Fetal Medicine Foundation (FMF) first trimester prediction model (namely the triple test), which consists of a combination of maternal factors and measurements of mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor, has undergone successful internal and external validation. The FMF triple test has detection rates of 90% and 75% for the prediction of early and preterm preeclampsia, respectively, with a 10% false-positive rate. Such performance of screening is superior to that of the traditional method by maternal risk factors alone. The use of the FMF prediction model, followed by the administration of low-dose aspirin, has been shown to reduce the rate of preterm preeclampsia by 62%. The number needed to screen to prevent 1 case of preterm preeclampsia by the FMF triple test is 250. The key to maintaining optimal screening performance is to establish standardized protocols for biomarker measurements and regular biomarker quality assessment, as inaccurate measurement can affect screening performance. Tools frequently used to assess quality control include the cumulative sum and target plot. Cumulative sum is a sensitive method to detect small shifts over time, and point of shift can be easily identified. Target plot is a tool to evaluate deviation from the expected multiple of median and the expected median of standard deviation. Target plot is easy to interpret and visualize. However, it is insensitive to detecting small deviations. Adherence to well-defined protocols for the measurements of mean arterial pressure, uterine artery pulsatility index, and placental growth factor is required. This article summarizes the existing literature on the different methods, recommendations by professional organizations, quality assessment of different components of risk assessment, and clinical implementation of the first trimester screening for preeclampsia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2020.07.020DOI Listing
July 2020

Feasibility, Reliability, and Agreement of Transperineal Ultrasound Measurement: Results from a Longitudinal Cohort Study.

Fetal Diagn Ther 2020 Jul 7:1-10. Epub 2020 Jul 7.

Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, Hong Kong,

Objectives: To evaluate the feasibility, reliability, and agreement of serial transperineal ultrasound (TPU) assessment of fetal head station (parasagittal angle of progression [psAOP], head-perineum distance [HPD], and head-symphysis distance [HSD]) and sonographic cervical dilatation (SCD), compared to fetal head station and cervical dilatation determined by vaginal examination, respectively.

Methods: This was a prospective longitudinal study in singleton pregnancies undergoing induction of labor at term. Paired assessment of fetal head station and cervical dilatation by vaginal examination, with TPU assessment of psAOP, HPD, HSD, and SCD was made serially. Feasibility, correlation, reliability, and agreement were determined.

Results: 1,139 paired measurements among 326 women were included. psAOP and HPD were achievable in all assessments. HSD was not achievable in 3.4% (11/326) due to high fetal head station. Fetal head station by vaginal examination was positively correlated with psAOP (rho = 0.70) but negatively correlated with HPD (rho = -0.57) and HSD (rho = -0.52). The feasibility to measure SCD reduced as cervical dilatation increased. Cervical dilatation and SCD were positively correlated (rho = 0.96) with strong agreement (concordant correlation coefficient = 0.925).

Conclusions: Measurements of psAOP and HPD are feasible and correlate significantly with fetal head station by vaginal examination. Measurement of HSD is not feasible when fetal head station is high. Measurement of SCD is feasible, but it is more difficult in the advanced stage of labor. The correlation, reliability, and agreement between SCD and cervical dilatation by vaginal examination are high.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000507549DOI Listing
July 2020

Coronavirus disease 2019 in pregnant women: a report based on 116 cases.

Am J Obstet Gynecol 2020 07 23;223(1):111.e1-111.e14. Epub 2020 Apr 23.

Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China. Electronic address:

Background: The coronavirus disease 2019, caused by severe acute respiratory syndrome coronavirus 2, is a global public health emergency. Data on the effect of coronavirus disease 2019 in pregnancy are limited to small case series.

Objective: To evaluate the clinical characteristics and outcomes in pregnancy and the vertical transmission potential of severe acute respiratory syndrome coronavirus 2 infection.

Study Design: Clinical records were retrospectively reviewed for 116 pregnant women with coronavirus disease 2019 pneumonia from 25 hospitals in China between January 20, 2020, and March 24, 2020. Evidence of vertical transmission was assessed by testing for severe acute respiratory syndrome coronavirus 2 in amniotic fluid, cord blood, and neonatal pharyngeal swab samples.

Results: The median gestational age on admission was 38 (interquartile range, 36-39) weeks. The most common symptoms were fever (50.9%, 59/116) and cough (28.4%, 33/116); 23.3% (27/116) patients presented without symptoms. Abnormal radiologic findings were found in 96.3% (104/108) of cases. Of the 116 cases, there were 8 cases (6.9%) of severe pneumonia but no maternal deaths. One of 8 patients who presented in the first trimester and early second trimester had a missed spontaneous abortion. Of 99 patients, 21 (21.2%) who delivered had preterm birth, including 6 with preterm premature rupture of membranes. The rate of spontaneous preterm birth before 37 weeks' gestation was 6.1% (6/99). One case of severe neonatal asphyxia resulted in neonatal death. Furthermore, 86 of the 100 neonates tested for severe acute respiratory syndrome coronavirus 2 had negative results; of these, paired amniotic fluid and cord blood samples from 10 neonates used to test for severe acute respiratory syndrome coronavirus 2 had negative results.

Conclusion: Severe acute respiratory syndrome coronavirus 2 infection during pregnancy is not associated with an increased risk of spontaneous abortion and spontaneous preterm birth. There is no evidence of vertical transmission of severe acute respiratory syndrome coronavirus 2 infection when the infection manifests during the third trimester of pregnancy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2020.04.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7177142PMC
July 2020

Shear-wave sonoelastographic assessment of cervix in pregnancy.

Acta Obstet Gynecol Scand 2020 11 15;99(11):1458-1468. Epub 2020 May 15.

Department of Obstetrics and gynecology, The Chinese University of Hong Kong, Hong Kong SAR.

Introduction: The aim of this study was to investigate the differences in shear-wave sonoelastography (SWS) scores between the different parts of cervix, explore the association between the cervical SWS scores with cervical length and evaluate repeatability of the measurement of cervical SWS scores.

Material And Methods: This was a prospective study performed in women with singleton pregnancy at 11-13 (n = 676), 16-20 (n = 364), 21-24 (n = 338) and 28-32 weeks (n = 304). The SWS scores were obtained at the inner, middle and external parts of the cervix, using a transvaginal ultrasound approach.

Results: The SWS scores of the inner cervix were significantly higher than the measurements acquired at the middle and external parts (all P < .001). At 21-24 and 28-32 weeks, most regions of interest demonstrated a very weak positive correlation with cervical length (r = .125 to r = .299). In comparison with nulliparous women, parous women without prior preterm birth had higher SWS scores of the inner and middle parts of the cervix at 16-20 and 21-24 weeks. All regions of interest showed good intra- and inter-observer agreement.

Conclusions: The assessment of the cervical SWS scores is highly reproducible. The stiffness of the cervix demonstrates a gradient that decreases from the inner part to the external part and a very weak positive correlation with cervical length.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/aogs.13874DOI Listing
November 2020

Prelabor short-term variability in fetal heart rate by computerized cardiotocogram and maternal fetal doppler indices for the prediction of labor outcomes.

J Matern Fetal Neonatal Med 2020 Apr 14:1-10. Epub 2020 Apr 14.

Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.

To investigate (i) the association between pre-labor maternal-fetal Dopplers and fetal heart rate short-term variability (FHR STV) with arterial cord blood pH and (ii) the potential value of pre-labor maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria in predicting composite neonatal morbidity at term in a cohort of unselected women. A prospective study in 218 women with term singleton pregnancy in latent phase of labor or due to undergo induction of labor. Data on maternal characteristics, maternal-fetal Dopplers indices and computerized cardiotocography (CTG) findings of FHR STV and Dawes-Redman criteria were collected. Pearson correlation analysis was used to determine the relationship between maternal-fetal Dopplers and FHR STV and arterial cord blood pH. Logistic regression analysis was used to determine which factors amongst maternal characteristics, labor onset, indication of labor induction, estimated fetal weight (EFW), maternal-fetal Dopplers, FHR STV and Dawes-Redman criteria were significant predictors of composite neonatal morbidity and arterial cord blood pH less than 7.2. Of the 218 cases, 12 (5.5%) women were delivered by emergency operative delivery for pathological CTG, and 42 babies (19.3%) had composite neonatal morbidities. Arterial cord blood pH was not associated with maternal-fetal Doppler indices and FHR STV, but rather it was associated with maternal age and body mass index. The composite neonatal morbidity and arterial cord blood pH less than 7.2 were not significantly associated with maternal characteristics, labor onset, indication of labor induction, pre-labor assessment of EFW, maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria by computerized CTG. In unselected women in latent phase of labor or undergoing induction of labor at term, admission maternal-fetal Doppler indices, FHR STV and Dawes-Redman criteria are not predictive of composite neonatal morbidity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/14767058.2020.1752657DOI Listing
April 2020

Plasma DNA End-Motif Profiling as a Fragmentomic Marker in Cancer, Pregnancy, and Transplantation.

Cancer Discov 2020 May 28;10(5):664-673. Epub 2020 Feb 28.

Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.

Plasma DNA fragmentomics is an emerging area of research covering plasma DNA sizes, end points, and nucleosome footprints. In the present study, we found a significant increase in the diversity of plasma DNA end motifs in patients with hepatocellular carcinoma (HCC). Compared with patients without HCC, patients with HCC showed a preferential pattern of 4-mer end motifs. In particular, the abundance of plasma DNA motif CCCA was much lower in patients with HCC than in subjects without HCC. The aberrant end motifs were also observed in patients with other cancer types, including colorectal cancer, lung cancer, nasopharyngeal carcinoma, and head and neck squamous cell carcinoma. We further observed that the profile of plasma DNA end motifs originating from the same organ, such as the liver, placenta, and hematopoietic cells, generally clustered together. The profile of end motifs may therefore serve as a class of biomarkers for liquid biopsy in oncology, noninvasive prenatal testing, and transplantation monitoring. SIGNIFICANCE: Plasma DNA molecules originating from the liver, HCC and other cancers, placenta, and hematopoietic cells each harbor a set of characteristic plasma DNA end motifs. Such markers carry tissue-of-origin information and represent a new class of biomarkers in the nascent field of fragmentomics..
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/2159-8290.CD-19-0622DOI Listing
May 2020

The predictive value of cervical shear wave elastography in the outcome of labor induction.

Acta Obstet Gynecol Scand 2020 01 5;99(1):59-68. Epub 2019 Nov 5.

Department of Obstetrics and Gynecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, SAR, China.

Introduction: Bishop score, the traditional method to assess cervical condition, is not a promising predictive tool of the outcome of labor induction. As an objective assessment tool, many cervical ultrasound measurements have been proposed to represent the individual components of the Bishop score, but none of them can measure the cervical stiffness. Cervical shear wave elastography is a novel tool to assess the cervical stiffness quantitatively.

Material And Methods: A total of 475 women who required labor induction were studied prospectively. Prior to routine digital assessment of the Bishop score, transvaginal sonographic measurement of cervical length, posterior cervical angle, angle of progression and shear wave elastography was performed. Shear wave elastography measurement was made at the inner, middle and outer regions of the cervix to assess homogeneity. Association of labor induction outcomes including the overall cesarean section and subgroups of cesarean section for failure to enter active phase, with cervical sonographic parameters and the Bishop score, were assessed using multivariate regression analyses. The predictive accuracy of the outcomes using models based on ultrasound measurement and the Bishop score was compared using the area under the receiver-operating characteristics curves.

Results: Among 475 women, 82 (17.3%) required cesarean section. Shear wave elasticity was significantly higher in the inner cervical region than in other regions, indicating a greater stiffness (P < 0.001). Both inner cervical shear wave elasticity and cervical length were independent predictors of overall cesarean section (respective adjusted odds ratio [95% CI] 1.338 [1.001-1.598] and 1.717 [1.077-1.663]) and cesarean section for failure to enter active phase (respective adjusted odds ratio [95% CI] 1.689 [1.234-2.311] and 2.556 [1.462-4.467]), after adjusting for other covariates. Outcome prediction models using inner cervical shear wave elasticity and cervical length, had increased area under curve compared with models using the Bishop score (0.888 vs 0.819, P = 0.009).

Conclusions: The cervix is not a homogenous structure, with the inner cervix having the highest stiffness, which is an independent predictor of overall cesarean section, and specifically for those indicated because of failure to enter active phase. Models based on shear wave elastography and cervical length had higher predictive accuracy than models based on the Bishop score.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/aogs.13706DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6973099PMC
January 2020

Prospective evaluation of screening performance of first-trimester prediction models for preterm preeclampsia in an Asian population.

Am J Obstet Gynecol 2019 12 4;221(6):650.e1-650.e16. Epub 2019 Oct 4.

Chinese University of Hong Kong, Hong Kong SAR, China. Electronic address:

Background: The administration of aspirin <16 weeks gestation to women who are at high risk for preeclampsia has been shown to reduce the rate of preterm preeclampsia by 65%. The traditional approach to identify such women who are at risk is based on risk factors from maternal characteristics, obstetrics, and medical history as recommended by the American College of Obstetricians and Gynecologists and the National Institute for Health and Care Excellence. An alternative approach to screening for preeclampsia has been developed by the Fetal Medicine Foundation. This approach allows the estimation of patient-specific risks of preeclampsia that requires delivery before a specified gestational age with the use of Bayes theorem-based model.

Objective: The purpose of this study was to examine the diagnostic accuracy of the Fetal Medicine Foundation Bayes theorem-based model, the American College of Obstetricians and Gynecologists, and the National Institute for Health and Care Excellence recommendations for the prediction of preterm preeclampsia at 11-13 weeks gestation in a large Asian population STUDY DESIGN: This was a prospective, nonintervention, multicenter study in 10,935 singleton pregnancies at 11-13 weeks gestation in 11 recruiting centers across 7 regions in Asia between December 2016 and June 2018. Maternal characteristics and medical, obstetric, and drug history were recorded. Mean arterial pressure and uterine artery pulsatility indices were measured according to standardized protocols. Maternal serum placental growth factor concentrations were measured by automated analyzers. The measured values of mean arterial pressure, uterine artery pulsatility index, and placental growth factor were converted into multiples of the median. The Fetal Medicine Foundation Bayes theorem-based model was used for the calculation of patient-specific risk of preeclampsia at <37 weeks gestation (preterm preeclampsia) and at any gestation (all preeclampsia) in each participant. The performance of screening for preterm preeclampsia and all preeclampsia by a combination of maternal factors, mean arterial pressure, uterine artery pulsatility index, and placental growth factor (triple test) was evaluated with the adjustment of aspirin use. We examined the predictive performance of the model by the use of receiver operating characteristic curve and calibration by measurements of calibration slope and calibration in the large. The detection rate of screening by the Fetal Medicine Foundation Bayes theorem-based model was compared with the model that was derived from the application of American College of Obstetricians and Gynecologists and National Institute for Health and Care Excellence recommendations.

Results: There were 224 women (2.05%) who experienced preeclampsia, which included 73 cases (0.67%) of preterm preeclampsia. In pregnancies with preterm preeclampsia, the mean multiples of the median values of mean arterial pressure and uterine artery pulsatility index were significantly higher (mean arterial pressure, 1.099 vs 1.008 [P<.001]; uterine artery pulsatility index, 1.188 vs 1.063[P=.006]), and the mean placental growth factor multiples of the median was significantly lower (0.760 vs 1.100 [P<.001]) than in women without preeclampsia. The Fetal Medicine Foundation triple test achieved detection rates of 48.2%, 64.0%, 71.8%, and 75.8% at 5%, 10%, 15%, and 20% fixed false-positive rates, respectively, for the prediction of preterm preeclampsia. These were comparable with those of previously published data from the Fetal Medicine Foundation study. Screening that used the American College of Obstetricians and Gynecologists recommendations achieved detection rate of 54.6% at 20.4% false-positive rate. The detection rate with the use of National Institute for Health and Care Excellence guideline was 26.3% at 5.5% false-positive rate.

Conclusion: Based on a large number of women, this study has demonstrated that the Fetal Medicine Foundation Bayes theorem-based model is effective in the prediction of preterm preeclampsia in an Asian population and that this method of screening is superior to the approach recommended by American College of Obstetricians and Gynecologists and the National Institute for Health and Care Excellence. We have also shown that the Fetal Medicine Foundation prediction model can be implemented as part of routine prenatal care through the use of the existing infrastructure of routine prenatal care.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2019.09.041DOI Listing
December 2019

Does low-dose aspirin initiated before 11 weeks' gestation reduce the rate of preeclampsia?

Am J Obstet Gynecol 2020 05 5;222(5):437-450. Epub 2019 Sep 5.

Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.

Objective Data: Preconception or early administration of low-dose aspirin might improve endometrial growth, placental vascularization, and organogenesis. Most studies have evaluated the potential benefit of preconception or early administration of low-dose aspirin in women with a history of recurrent pregnancy loss, women who have undergone in vitro fertilization, or women with thrombophilia or antiphospholipid syndrome. These women are at an increased risk of placenta-associated complications of pregnancy, including preeclampsia, preterm delivery, and fetal growth restriction.

Study Outcomes: We performed a systematic review and meta-analysis to evaluate the effect of low-dose aspirin initiated at <11 weeks' gestation on the risk of preeclampsia, gestational hypertension, or any hypertensive disorder of pregnancy. Secondary outcomes included preterm delivery at <37 weeks' gestation and fetal growth restriction.

Study Appraisal And Synthesis Methods: We searched in MEDLINE via PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform from 1985 to November 2018. Entry criteria were randomized controlled trials evaluating the effect of aspirin administered at <11 weeks' gestation in preventing preeclampsia and/or hypertensive disorders in pregnancy or improving pregnancy outcomes in women with recurrent miscarriage as compared with placebo or no treatment and outcome data available or provided by authors for >85% of the study population. Relative risks with 95% confidence intervals were calculated for each study and pooled for global analysis as the effect measure. We assessed statistical heterogeneity in each meta-analysis using the χ statistics, I, and Tau. Heterogeneity was considered substantial if an I was greater than 50% and either the Tau was greater than zero or there was a low P value (<0.10) in the χ test for heterogeneity. Random-effects meta-analysis, weighted by the size of the studies, was performed to produce an overall summary on aspirin effect for each outcome. Sensitivity analysis by sequential omission of each individual study and by fixed-effects model was performed. Publication bias was not assessed because of the small number of included studies. Statistical analysis was performed using Stata release 14.0 (StataCorp).

Results: The entry criteria were fulfilled by 8 randomized controlled trials on a combined total of 1426 participants. Low-dose aspirin initiated at <11 weeks' gestation was associated with a nonsignificant reduction in the risk of preeclampsia (relative risk, 0.52; 95% confidence interval, 0.23-1.17, P = .115), gestational hypertension (relative risk, 0.49; 95% confidence interval, 0.20-1.21; P = .121), and any hypertensive disorder of pregnancy (relative risk, 0.59; 95% confidence interval, 0.33-1.04, P = .067). Early administration of low-dose aspirin reduced the risk of preterm delivery (relative risk, 0.52; 95% confidence interval, 0.27-0.97, P = .040) but had no impact on the risk of fetal growth restriction (relative risk, 1.10; 95% confidence interval, 0.58-2.07, P = .775). Except for preterm delivery and any hypertensive disorder of pregnancy, sensitivity analysis demonstrated similar observations, therefore confirming the robustness of the analysis.

Conclusion: The administration of low-dose aspirin at <11 weeks' gestation in women at high risk does not decrease the risk of preeclampsia, gestational hypertension, any hypertensive disorder of pregnancy, and fetal growth restriction. However, it might reduce the risk of preterm delivery. Larger randomized controlled trials will be required to substantiate the findings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2019.08.047DOI Listing
May 2020

Reasons for accepting or declining participation in the ASPRE trial: A qualitative study with women at high risk of preterm pre-eclampsia.

Prenat Diagn 2019 11 13;39(12):1127-1135. Epub 2019 Sep 13.

Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.

Objective: To identify factors that affected the decision of pregnant women at high risk for pre-eclampsia (PE) in accepting or declining participation in a medicated clinical trial (ASPRE) for the prevention of preterm PE.

Method: This was a qualitative, cross-sectional study. A purposive sample of 14 participants and 13 decliners of the ASPRE trial were interviewed using semi-structured interviews. Data were analysed using template analysis.

Results: For participants, their high-risk status seems to have motivated them to take part in the trial. This was enabled by their perception that the trial drug aspirin was commonly used, the safety of the procedure, and the belief that they will be in receipt of extra monitoring in pregnancy. Decliners expressed discomfort about taking medications in pregnancy, and about the presence of the placebo arm; they seemed to be motivated by desire to reduce harm. Satisfaction with the information provided by the medical professionals was also influential in women's decision making, and so were the views of their partners and other trusted individuals.

Conclusion: Pregnant women's motivation to take part or to decline participation in a medicated trail can be understood as an attempt to cope with the threat posed by their high-risk status.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pd.5554DOI Listing
November 2019

Labor progress determined by ultrasound is different in women requiring cesarean delivery from those who experience a vaginal delivery following induction of labor.

Am J Obstet Gynecol 2019 10 30;221(4):335.e1-335.e18. Epub 2019 May 30.

Department of Obstetrics and Gynaecology, Prince of Wales Hospital, The Chinese University of Hong Kong, Sha Tin, Hong Kong. Electronic address:

Background: The diagnosis of labor dystocia generally is determined by the deviation of labor progress, which is assessed by the use of a partogram. Recently, intrapartum transperineal ultrasound for the assessment of fetal head descent has been introduced to assess labor progress in the first stage of labor in a more objective and noninvasive way.

Objective: The objective of the study was to determine the differences in labor progress by the use of serial transperineal ultrasound assessment of fetal head descent between women having vaginal and cesarean delivery.

Study Design: This was a prospective longitudinal study performed in 315 women with singleton pregnancy who were undergoing labor induction at term between December 2016 and December 2017. Paired assessment of cervical dilation and fetal head station by vaginal examination and transperineal ultrasonographic assessment of parasagittal angle of progression and head-perineum distance were made serially after the commencement of labor induction. According to the hospital protocol, assessment was performed every 24 hours and 4 hours, respectively, during latent and active phases of labor. The researchers and the clinical team were blinded to each other's findings. The repeated measures data were analyzed by mixed effect models. To determine the effect of mode of delivery on the association between parasagittal angle of progression and head-perineum distance against fetal head station and cervical dilation, the significance of the interaction term between each mode of delivery and fetal head station or cervical dilation was determined, which accounted for parity and obesity. Area under receiver-operating characteristic curve was used to evaluate the performance of serial intrapartum sonography in predicting women with cesarean delivery because of failure to progress.

Results: The total number of paired vaginal examination and ultrasound assessments was 1198, with a median of 3 per woman. The median assessment-to-assessment interval was 4.6 hours (interquartile range, 4.3-5.1 hours). Women who achieved vaginal delivery (n=261) had steeper slopes of parasagittal angle of progression and head-perineum distance against fetal head station and cervical dilation than those who achieved cesarean delivery (n=54). Objectively, an additional decrease of 5.11 and 1.37 degrees in parasagittal angle of progression was observed for an unit increase in fetal head station and cervical dilation, respectively, in women who required cesarean delivery (P<.01; P=.01), compared with women who achieved vaginal delivery, after taking account of repeated measures from individuals and confounding factors. The respective additional increases in head-perineum distance for a unit increase in fetal head station and cervical dilation were 0.27 cm (P<.01) and 0.12 cm (P<.01). A combination of maternal characteristics with the temporal changes of parasagittal angle of progression for an unit increase in fetal head station achieved an area under receiver-operating characteristic curve of 0.85 (95% confidence interval, 0.76-0.94), with sensitivity of 79% and specificity of 80%, for the prediction of women who required cesarean delivery because of failure to progress.

Conclusion: The differences in labor progress between vaginal and cesarean delivery have been illustrated objectively by serial intrapartum transperineal ultrasonographic assessment of fetal head descent. This tool is potentially predictive of women who will require cesarean delivery because of failure to progress.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2019.05.040DOI Listing
October 2019

The International Federation of Gynecology and Obstetrics (FIGO) initiative on pre-eclampsia: A pragmatic guide for first-trimester screening and prevention.

Int J Gynaecol Obstet 2019 05;145 Suppl 1:1-33

Helen Schneider Hospital for Women, Rabin Medical Center, Petah Tikva, and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Pre‐eclampsia (PE) is a multisystem disorder that typically affects 2%–5% of pregnant women and is one of the leading causes of maternal and perinatal morbidity and mortality, especially when the condition is of early onset. Globally, 76 000 women and 500 000 babies die each year from this disorder. Furthermore, women in low‐resource countries are at a higher risk of developing PE compared with those in high‐resource countries. Although a complete understanding of the pathogenesis of PE remains unclear, the current theory suggests a two‐stage process. The first stage is caused by shallow invasion of the trophoblast, resulting in inadequate remodeling of the spiral arteries. This is presumed to lead to the second stage, which involves the maternal response to endothelial dysfunction and imbalance between angiogenic and antiangiogenic factors, resulting in the clinical features of the disorder. Accurate prediction and uniform prevention continue to elude us. The quest to effectively predict PE in the first trimester of pregnancy is fueled by the desire to identify women who are at high risk of developing PE, so that necessary measures can be initiated early enough to improve placentation and thus prevent or at least reduce the frequency of its occurrence. Furthermore, identification of an “at risk” group will allow tailored prenatal surveillance to anticipate and recognize the onset of the clinical syndrome and manage it promptly. PE has been previously defined as the onset of hypertension accompanied by significant proteinuria after 20 weeks of gestation. Recently, the definition of PE has been broadened. Now the internationally agreed definition of PE is the one proposed by the International Society for the Study of Hypertension in Pregnancy (ISSHP). According to the ISSHP, PE is defined as systolic blood pressure at ≥140 mm Hg and/or diastolic blood pressure at ≥90 mm Hg on at least two occasions measured 4 hours apart in previously normotensive women and is accompanied by one or more of the following new‐onset conditions at or after 20 weeks of gestation: 1.Proteinuria (i.e. ≥30 mg/mol protein:creatinine ratio; ≥300 mg/24 hour; or ≥2 + dipstick); 2.Evidence of other maternal organ dysfunction, including: acute kidney injury (creatinine ≥90 μmol/L; 1 mg/dL); liver involvement (elevated transaminases, e.g. alanine aminotransferase or aspartate aminotransferase >40 IU/L) with or without right upper quadrant or epigastric abdominal pain; neurological complications (e.g. eclampsia, altered mental status, blindness, stroke, clonus, severe headaches, and persistent visual scotomata); or hematological complications (thrombocytopenia–platelet count <150 000/μL, disseminated intravascular coagulation, hemolysis); or 3.Uteroplacental dysfunction (such as fetal growth restriction, abnormal umbilical artery Doppler waveform analysis, or stillbirth). It is well established that a number of maternal risk factors are associated with the development of PE: advanced maternal age; nulliparity; previous history of PE; short and long interpregnancy interval; use of assisted reproductive technologies; family history of PE; obesity; Afro‐Caribbean and South Asian racial origin; co‐morbid medical conditions including hyperglycemia in pregnancy; pre‐existing chronic hypertension; renal disease; and autoimmune diseases, such as systemic lupus erythematosus and antiphospholipid syndrome. These risk factors have been described by various professional organizations for the identification of women at risk of PE; however, this approach to screening is inadequate for effective prediction of PE. PE can be subclassified into: 1.Early‐onset PE (with delivery at <34+0 weeks of gestation); 2.Preterm PE (with delivery at <37+0 weeks of gestation); 3.Late‐onset PE (with delivery at ≥34+0 weeks of gestation); 4.Term PE (with delivery at ≥37+0 weeks of gestation). These subclassifications are not mutually exclusive. Early‐onset PE is associated with a much higher risk of short‐ and long‐term maternal and perinatal morbidity and mortality. Obstetricians managing women with preterm PE are faced with the challenge of balancing the need to achieve fetal maturation in utero with the risks to the mother and fetus of continuing the pregnancy longer. These risks include progression to eclampsia, development of placental abruption and HELLP (hemolysis, elevated liver enzyme, low platelet) syndrome. On the other hand, preterm delivery is associated with higher infant mortality rates and increased morbidity resulting from small for gestational age (SGA), thrombocytopenia, bronchopulmonary dysplasia, cerebral palsy, and an increased risk of various chronic diseases in adult life, particularly type 2 diabetes, cardiovascular disease, and obesity. Women who have experienced PE may also face additional health problems in later life, as the condition is associated with an increased risk of death from future cardiovascular disease, hypertension, stroke, renal impairment, metabolic syndrome, and diabetes. The life expectancy of women who developed preterm PE is reduced on average by 10 years. There is also significant impact on the infants in the long term, such as increased risks of insulin resistance, diabetes mellitus, coronary artery disease, and hypertension in infants born to pre‐eclamptic women. The International Federation of Gynecology and Obstetrics (FIGO) brought together international experts to discuss and evaluate current knowledge on PE and develop a document to frame the issues and suggest key actions to address the health burden posed by PE. FIGO's objectives, as outlined in this document, are: (1) To raise awareness of the links between PE and poor maternal and perinatal outcomes, as well as to the future health risks to mother and offspring, and demand a clearly defined global health agenda to tackle this issue; and (2) To create a consensus document that provides guidance for the first‐trimester screening and prevention of preterm PE, and to disseminate and encourage its use. Based on high‐quality evidence, the document outlines current global standards for the first‐trimester screening and prevention of preterm PE, which is in line with FIGO good clinical practice advice on first trimester screening and prevention of pre‐eclampsia in singleton pregnancy.1 It provides both the best and the most pragmatic recommendations according to the level of acceptability, feasibility, and ease of implementation that have the potential to produce the most significant impact in different resource settings. Suggestions are provided for a variety of different regional and resource settings based on their financial, human, and infrastructure resources, as well as for research priorities to bridge the current knowledge and evidence gap. To deal with the issue of PE, FIGO recommends the following: Public health focus: There should be greater international attention given to PE and to the links between maternal health and noncommunicable diseases (NCDs) on the Sustainable Developmental Goals agenda. Public health measures to increase awareness, access, affordability, and acceptance of preconception counselling, and prenatal and postnatal services for women of reproductive age should be prioritized. Greater efforts are required to raise awareness of the benefits of early prenatal visits targeted at reproductive‐aged women, particularly in low‐resource countries. Universal screening: All pregnant women should be screened for preterm PE during early pregnancy by the first‐trimester combined test with maternal risk factors and biomarkers as a one‐step procedure. The risk calculator is available free of charge at https://fetalmedicine.org/research/assess/preeclampsia. FIGO encourages all countries and its member associations to adopt and promote strategies to ensure this. The best combined test is one that includes maternal risk factors, measurements of mean arterial pressure (MAP), serum placental growth factor (PLGF), and uterine artery pulsatility index (UTPI). Where it is not possible to measure PLGF and/or UTPI, the baseline screening test should be a combination of maternal risk factors with MAP, and not maternal risk factors alone. If maternal serum pregnancy‐associated plasma protein A (PAPP‐A) is measured for routine first‐trimester screening for fetal aneuploidies, the result can be included for PE risk assessment. Variations to the full combined test would lead to a reduction in the performance screening. A woman is considered high risk when the risk is 1 in 100 or more based on the first‐trimester combined test with maternal risk factors, MAP, PLGF, and UTPI. Contingent screening: Where resources are limited, routine screening for preterm PE by maternal factors and MAP in all pregnancies and reserving measurements of PLGF and UTPI for a subgroup of the population (selected on the basis of the risk derived from screening by maternal factors and MAP) can be considered. Prophylactic measures: Following first‐trimester screening for preterm PE, women identified at high risk should receive aspirin prophylaxis commencing at 11–14+6 weeks of gestation at a dose of ~150 mg to be taken every night until 36 weeks of gestation, when delivery occurs, or when PE is diagnosed. Low‐dose aspirin should not be prescribed to all pregnant women. In women with low calcium intake (<800 mg/d), either calcium replacement (≤1 g elemental calcium/d) or calcium supplementation (1.5–2 g elemental calcium/d) may reduce the burden of both early‐ and late‐onset PE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ijgo.12802DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6944283PMC
May 2019

The effect of parity on longitudinal maternal hemodynamics.

Am J Obstet Gynecol 2019 09 2;221(3):249.e1-249.e14. Epub 2019 Apr 2.

Fetal Medicine Research Institute, King's College London, London UK. Electronic address:

Background: Parous women have a lower risk for pregnancy complications, such as preeclampsia or delivery of small-for-gestational-age neonates. However, parous women are a heterogeneous group of patients because they contain a low-risk cohort with previously uncomplicated pregnancies and a high-risk cohort with previous pregnancies complicated by preeclampsia and/or small for gestational age. Previous studies examining the effect of parity on maternal hemodynamics, including cardiac output and peripheral vascular resistance, did not distinguish between parous women with and without a history of preeclampsia or small for gestational age and reported contradictory results.

Objective: The objective of the study was to compare maternal hemodynamics in nulliparous women and in parous women with and without previous preeclampsia and/or small for gestational age.

Study Design: This was a prospective, longitudinal study of maternal hemodynamics, assessed by a bioreactance method, measured at 11 to 13, 19 to 24, 30 to 34, and 35 to 37 weeks' gestation in 3 groups of women. Group 1 was composed of parous women without a history of preeclampsia and/or small for gestational age (n = 632), group 2 was composed of nulliparous women (n = 829), and group 3 was composed of parous women with a history of preeclampsia and/or small for gestational age (n = 113). A multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables controlling for maternal characteristics, medical history, and development of preeclampsia or small for gestational age in the current pregnancy.

Results: In groups 1 and 2, cardiac output increased with gestational age to a peak at 32 weeks and peripheral vascular resistance showed a reversed pattern with its nadir at 32 weeks; in group 1, compared with group 2, there was better cardiac adaptation, reflected in higher cardiac output and lower peripheral vascular resistance. In group 3 there was a hyperdynamic profile of higher cardiac output and lower peripheral vascular resistance at the first trimester followed by an earlier sharp decline of cardiac output and increase of peripheral vascular resistance from midgestation. The incidence of preeclampsia and small for gestational age was highest in group 3 and lowest in group 1.

Conclusion: There are parity-specific differences in maternal cardiac adaptation in pregnancy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajog.2019.03.027DOI Listing
September 2019