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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.

Background Placenta previa remains one of the major causes of massive postpartum hemorrhage and maternal mortality worldwide. Objective To determine whether internal iliac artery balloon occlusion during cesarean delivery for placenta previa could reduce postpartum hemorrhage and other maternal complications. Study Design This was a prospective randomized controlled trial conducted at a tertiary university obstetric unit in Hong Kong. Pregnant women who were diagnosed to have placenta previa at 34 weeks (defined as lower placenta edge within 2 cm from the internal os) and required cesarean delivery were invited to participate. Eligible pregnant women were randomized into internal iliac artery balloon occlusion (Occlusion) group or standard management (Control) group. Those randomized to the Occlusion group had internal iliac artery balloon catheter placement performed before cesarean delivery and then balloon inflation after delivery of the baby. The primary outcome was the reduction of postpartum hemorrhage in those with internal iliac artery balloon occlusion. Secondary outcome measures included hemoglobin drop after delivery; amount of blood product transfusion; incidence of hysterectomy; maternal complications including renal failure, ischemic liver, disseminated intravascular coagulation, and adult respiratory distress syndrome; length of stay in hospital; admission to intensive care unit; and maternal death. Results Between May 2016 and September 2018, 40 women were randomized (20 in each group). Demographic and obstetric characteristics were similar between the 2 groups. In the Occlusion group, 3 women did not receive the scheduled procedure, as it was preceded by antepartum hemorrhage that required emergency cesarean delivery, and 1 woman had repeated scan at 36 weeks showing the placental edge was slightly more than 2 cm from the internal os. Intention-to-treat analysis found no significant differences between the Occlusion and the Control groups regarding to the median intraoperative blood loss (1451 [1024–2388] mL vs 1454 [888–2300] mL; P = .945), the median length of surgery (49 [30–62] min vs 37 [30–51] min; P = .204), or the need for blood transfusion during operation (57.9% vs 50.0%; P = .621). None of the patients had rebleeding after operation, complication related to internal iliac artery procedure, or any other maternal complications. Reanalyzing the data using on-treatment approach showed the same results. Conclusion The use of prophylactic internal iliac artery balloon occlusion in placenta previa patients undergoing cesarean delivery did not reduce postpartum hemorrhage or have any effect on maternal or neonatal morbidity.

The administration of aspirin16 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.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 11-13There 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.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.

Objective The purpose of this study was to assess the prevalence of female urinary tract infection before and after urodynamic investigation and to identify the risk factors for urinary tract infection after urodynamic investigation. Study design Eight hundred twenty-two consecutive incontinent women were recruited. All women were “double-screened” and treated for urinary tract infection before urodynamic investigation: first by mid stream urine culture 4 to 6 weeks before investigation and then by reagent strips for urine leukocytes and nitrites at the time of investigation. The investigation was postponed until the urinary tract infection had been treated. All women then received a standard urodynamic investigation. Results The prevalence of urinary tract infection before urodynamic investigation was 5.1% (95% CI, 3.6-6.6), and the prevalence after the investigation was 8.4% (95% CI, 6.5-10.3). Three independent risk factors were identified: age ≥70 years (odds ratio, 1.99; 95% CI, 1.14-3.48), previous continence surgery (odds ratio, 1.90; 95% CI, 1.05-3.43), and urinary tract infection before urodynamic investigation (odds ratio, 3.13; 95% CI, 1.43-6.83). The 3 most common uropathogens in the urinary tract infections after the urodynamic investigation were Escherichia coli (46.3%), Enterococcus spp (16.4%), and Enterococcus faecalis (11.9%). Conclusion Despite a stringent screen-and-treat protocol before urodynamic investigation, patients still experienced urinary tract infection.

Objective: The purpose of this study was to evaluate the long-term prevalence of urinary incontinence in women with postpartum urinary retention. Study Design: A telephone interview was conducted by contacting a cohort of 691 women who delivered vaginally 4 years ago, of which 101 women had been diagnosed as having postpartum urinary retention. A structured telephone interview consisted of 9 questions on the possible outcomes of postpartum urinary retention. Results: Of the original cohort of 691 women, 394 women were contacted. Seventy-three women had had postpartum urinary retention, and 321 women had not. In women who had had postpartum urinary retention, the prevalence of the outcome variables were urinary stress incontinence (28.8%), fecal incontinence (2.7%), frequency (39.1%), nocturia (65.2%), urgency (26.1%), urge incontinence (26.1%), and coital incontinence (13%). Analyses showed that there was no significant difference between women with and without urinary retention. Conclusion: Women who had had postpartum urinary retention did not have a higher prevalence of urinary stress incontinence. (Am J Obstet Gynecol 2002;187:648-52.)

Objective: To investigate the acute and chronic changes in fetal heart rate and fetal activity in association with maternal smoking by means of a computerized fetal behavior assessment program. Study Design: In 13 term nonsmokers and 13 term smokers, fetal behavior was analyzed for 2 consecutive periods of >60 minutes. In between these 2 periods, the smokers were allowed to smoke 1 cigarette, the nonsmokers were allowed a short break of comparable time span. Fetal heart rate variation and fetal activity were recorded by a single 1.5-MHZ ultrasound transducer. The percentage of time spent in low and high fetal heart rate variation and fetal activity were analyzed by computer before and after the short break for nonsmokers and before and after the smokers smoked the 1 cigarette. Smoking-induced changes in Doppler umbilical artery recordings were also investigated. Chronic exposure to cigarette smoke was objectively evaluated by measuring the carbon monoxide concentration in expired air in all participating women after breath holding. Results: Fetuses chronically exposed to cigarette smoke spent significantly more time in a low fetal heart rate variation pattern, while fetal activity was decreased both in high and low fetal heart rate variation periods. After maternal smoking, no acute changes were observed in fetal heart rate variation, yet a reduction in fetal activity was noted; however, this only reached statistical significance in periods of high fetal heart rate variation. No significant change in mean fetal heart rate was observed, yet a significant reduction in the frequency of accelerations was noted. Smoking caused an acute and transient increase in the mean pulsatility index in the umbilical artery. Conclusion: The computer program was able to detect changes in fetal behavioral variables in association with acute and chronic smoking. These changes may be suggestive of altered neurodevelopmental maturation possibly resulting from chronic fetal hypoxemia. This computer program offers a real possibility that analysis of fetal behavioral variables can be brought into routine clinical practice. Incorporating an analysis of these behavioral variables into smoking cessation programs may render them more successful. (Am J Obstet Gynecol 2001;185:421-6.)

Our goal was to test the hypothesis that the addition of fetal electrocardiogram time-interval analysis to conventional electronic fetal monitoring would significantly reduce the number of cases requiring fetal scalp blood sampling without an increase in adverse outcome.A randomized prospective trial was performed in 214 women with high-risk labor.There was a significant reduction in the number of cases that had fetal blood sampling performed in the fetal electrocardiogram plus electronic fetal monitoring group (risk ratio for electronic fetal monitoring alone 3.53; p0.01, 95% confidence interval 1.39 to 8.95). The fetal blood samplings performed in the electronic fetal monitoring alone group were less likely to be abnormal (pH7.25, base excess-8.0) than those performed in the fetal electrocardiogram plus electronic fetal monitoring group (risk ratio for electronic fetal monitoring alone 0.62, p = 0.05, 95% confidence interval 0.35 to 1.10). There was a trend of more infants with an arterial umbilical pH7.15 and a base excess less than -8.0 mmol/L at birth being unsuspected and more instrumental deliveries for presumed fetal distress being performed in the electronic fetal monitoring alone than in the fetal electrocardiogram plus electronic fetal monitoring group.The addition of fetal electrocardiogram analysis to conventional electronic fetal monitoring during labor can reduce significantly the number of parturients undergoing fetal scalp blood sampling and can simultaneously increase its efficiency without an increase in adverse outcome.

Objective: This study was undertaken to analyze the relationship between the fetal electrocardiogram and arterial pH and base excess at delivery. Study Design: In the labor wards of three teaching hospitals a retrospective observational study was conducted on fetal monitor recordings of 679 women for whom there was an indication for continuous fetal monitoring during labor. These women had been recruited as part of either observational studies or a prospective randomized trial related to the Nottingham fetal electrocardiographic project. Fetal heart and uterine contraction data were obtained with the Nottingham fetal electrocardiographic analyzer. Morphologic and time interval analyses of the fetal electrocardiogram were performed. Evaluation was carried out for the last half hour before delivery. Main outcome measures were umbilical arterial pH and base excess at delivery. Results: The study demonstrated a relationship between time interval analysis of the fetal electrocardiogram and a low umbilical arterial pH and base excess at delivery. Analysis of the morphologic characteristics of the fetal electrocardiogram (ST segment and T-wave height) showed no significant relationship. Conclusions: Time interval analysis of the fetal electrocardiogram during labor is related to relative acidemia at delivery. (Am J Obstet Gynecol 2000;182:603-6.)

Placentas were obtained at delivery from 34 pregnancies complicated by preeclampsia and from 34 uncomplicated pregnancies. The incidence of apoptotic nuclei was significantly greater (P

Objective The objective of the study was to determine the likelihood ratio for trisomy 21 in Chinese fetuses with absent nasal bone (NB) at 11-14 weeks of gestation. Study Design The NB was classified as present or absent in 8101 chromosomally/phenotypically normal or trisomy 21 pregnancies. The effect of crown rump length (CRL), nuchal translucency (NT), maternal age, and fetal karyotype on the incidence of absent NB was examined using logistic regression. Results The NB was successfully examined in 7925 cases (97.8%). The incidence of absent NB in unaffected and trisomy 21 cases were 2.1% (164/7899) and 50% (13/26), respectively. CRL (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.87-0.92), NT (OR, 1.7; 95% CI, 1.4-2.3), and trisomy 21 (OR, 22.3; 95% CI, 8.1-61) were significant independent predictors of likelihood of absent NB. Positive likelihood ratios (LR) for trisomy 21 in Chinese were lower than that of Caucasians for the equivalent CRL and NT measurements. Conclusion Estimated risk for trimsomy 21 in Chinese incorporating nasal bone status should use LRs derived in Chinese rather than Caucasians.