The Relation between Duration of Ruptured Membranes and Perinatal Outcome in Patients with Midtrimester Prelabor Rupture of Membranes.

OBJECTIVE: The aim of the study was to assess the impact of gestational age (GA) at rupture and latency on perinatal outcome after midtrimester prelabor rupture of membranes (PROM). STUDY DESIGN: We obtained data on singleton pregnancies from 22 weeks onwards from the Dutch Perinatal Registry from 1999 to 2007, congenital abnormalities were excluded. In women with PROM before 26 weeks, we studied the impact of GA at rupture and latency on perinatal mortality and morbidity. RESULTS: A total of 1,233 pregnancies were included. Higher GA at delivery appeared to increase the probability of survival without morbidity, GA at PROM did not. In pregnancies of minimum 22 weeks GA, there appeared to be no clear relationship between earlier GA at PROM and adverse outcome. CONCLUSION: Longer latency and early GA at PROM seem to have limited impact in patients delivering after 22 weeks.

Trends in birth asphyxia, obstetric interventions and perinatal mortality among term singletons: a nationwide cohort study.

OBJECTIVE: The objective of the present study is to investigate trends in birth asphyxia and perinatal mortality in the Netherlands over the last decade. METHODS: A nationwide cohort study among women with a term singleton pregnancy. We assessed trends in birth asphyxia in relation to obstetric interventions for fetal distress. Birth asphyxia was defined as a 5-minute Apgar score < 7 (any asphyxia) or 5-minute Apgar score < 4 (severe asphyxia). Perinatal mortality was defined as mortality during delivery or within 7 days after birth. Multivariable analyses were used to adjust for confounding factors. RESULTS: The prevalence of birth asphyxia was 0.85% and severe asphyxia 0.16%. Between 1999 and 2010 birth asphyxia decreased significantly with approximately 6% (p = 0.03) and severe asphyxia with 11% (p = 0.03). There was no significant change in perinatal mortality rate (0.98 per 1000 live births). Simultaneously the referral rate from primary to secondary care during labor increased from 20% to 24% (p < 0.0001) and the intervention rate for fetal distress from 5.9% to 7.7% (p < 0.0001). CONCLUSION: In the Netherlands, the risk of birth asphyxia among term singletons has slightly decreased over the last decade; without a significant change in perinatal mortality.

Trends in preterm birth in singleton deliveries in a Hong Kong population.

OBJECTIVE: To examine trends in preterm birth and its relationship with perinatal mortality in Hong Kong. METHODS: In a retrospective cohort study, data were reviewed from singletons delivered between 1995 and 2011 at a university teaching hospital. Trends in preterm birth (between 24 and 36 weeks of pregnancy), perinatal mortality, and subtypes of preterm birth (spontaneous, iatrogenic, and following preterm premature rupture of membranes [PPROM]) were examined via linear regression. RESULTS: There were 103 364 singleton deliveries, of which 6722 (6.5%) occurred preterm, including 1835 (1.8%) early preterm births (24-33 weeks) and 4887 (4.7%) late preterm births (34-36 weeks). Frequency of preterm birth remained fairly consistent over the study period, but that of spontaneous preterm birth decreased by 25% (ß=-0.83; P<0.001), from 4.5% to 3.8%. Frequency of preterm birth following PPROM increased by 135% (ß=0.82; P<0.001), from 0.7% to 1.7%. The perinatal mortality rate decreased from 56.7 to 37.0 deaths per 1000 deliveries before 37 weeks (ß=-0.16; P=0.54). Early preterm birth contributed to 16.0% of all deaths. CONCLUSION: Although the overall rate of preterm birth in Hong Kong has remained constant, the frequencies of its subtypes have changed. Overall perinatal mortality is gradually decreasing, but early preterm birth remains a major contributor.

Term breech deliveries in the Netherlands: did the increased cesarean rate affect neonatal outcome? A population-based cohort study.

OBJECTIVE: The aim of this study was to evaluate the effect of the increased cesarean rate for term breech presentation on neonatal outcome. We also investigated whether the clinical case selection for vaginal delivery applied by Dutch obstetricians led to an optimization of neonatal outcome, or whether there is still room for improvement in terms of perinatal outcome. DESIGN: Retrospective cohort. SETTING: The Netherlands. POPULATION: Singleton term breech deliveries from 37+0 to 41+6 weeks, excluding fetuses with congenital malformations or antenatal death. METHOD: We used data from the Dutch national perinatal registry from 1999 up to 2007. MAIN OUTCOME MEASURES: Perinatal mortality and morbidity. RESULTS: We studied 58,320 women with a term breech delivery. There was an increase in the elective cesarean rate (from 24 to 60%). As a consequence, overall perinatal mortality decreased [1.3 0/00 vs. 0.7 0/00;odds ratio 0.51 (95% confidence interval 0.28­0.93)], whereas it remained stable in the planned vaginal birth group [1.7 0/00 vs. 1.6 0/00; odds ratio 0.96(95% confidence interval 0.52­1.76)]. The number of cesareans done to prevent one perinatal death was 338. CONCLUSIONS: Adjustment of the national guidelines after publication of the Term Breech Trial resulted in a shift towards elective cesarean and a decrease of perinatal mortality and morbidity among women delivering a child in breech at term. Still, 40% of these women attempt vaginal birth. The relative safety of an elective cesarean should be weighed against the consequences of a scarred uterus in future pregnancies.

Recurrence risk of low Apgar score among term singletons: a population-based cohort study.

OBJECTIVE: To examine the risk of recurrence of low Apgar score in a subsequent term singleton pregnancy. DESIGN: Population-based cohort study. SETTING: The Netherlands. POPULATION: A total of 190,725 women with two subsequent singleton term live births between 1999 and 2007. METHODS: We calculated the recurrence risk of low Apgar score after adjustment for possible confounders. Women with an elective cesarean delivery, fetus in breech presentation or a fetus with congenital anomalies were excluded. Results were reported separately for women with a vaginal delivery or a cesarean delivery at first pregnancy. MAIN OUTCOME MEASURES: Prevalence of birth asphyxia, a 5-min Apgar score <7. RESULTS: The risk for an Apgar score of <7 in the first pregnancy was 0.99% and overall halved in the subsequent pregnancies (0.50%). For those with asphyxia in the first pregnancy, the risk of recurrence of a low Apgar score in the subsequent pregnancy was 1.1% (odds ratio 2.1, 95% confidence interval 1.4-3.3). This recurrence risk was present in women with a previous vaginal delivery (odds ratio 2.1, 95% confidence interval 1.2-3.5) and in women with a previous cesarean delivery (odds ratio 3.8, 95% confidence interval 1.7-8.5). Among women with a small-for-gestational-age infant in the subsequent pregnancy and a previous vaginal delivery, the recurrence risk was 4.8% (adjusted odds ratio 5.8, 95% confidence interval 2.0-16.5). CONCLUSION: Women with birth asphyxia of the first born have twice the risk of renewed asphyxia at the next birth compared to women without birth asphyxia of the first born. This should be incorporated in the risk assessment of pregnant women.

Antenatal prediction of neonatal mortality in very premature infants.

OBJECTIVE: To develop a prognostic model for antenatal prediction of neonatal mortality in infants threatening to be born very preterm (<32 weeks). STUDY DESIGN: Nationwide cohort study in The Netherlands between 1999 and 2007. We studied 8500 singletons born between 25(+0) and 31(+6) weeks of gestation where fetus was alive at birth without congenital anomalies. We developed a multiple logistic regression model to estimate the risk of neonatal mortality within 28 days after birth, based on characteristics that are known before birth. We used bootstrapping techniques for internal validation. Discrimination (AUC), accuracy (Brier score) and calibration (graph, c-statistics) were used to assess the model's predictive performance. RESULTS: Neonatal mortality occurred in 766 (90 per 1000) live births. The final model consisted of seven variables. Predictors were low gestational age, no antental corticosteroids, male gender, maternal age ≥35 years, Caucasian ethnicity, non-cephalic presentation and non-3rd level of hospital. The predicted probabilities ranged from 0.003 to 0.697 (IQR 0.02-0.11). The model had an AUC of 0.83, the Brier score was 0.065. The calibration graph showed good calibration, and the test for the Hosmer Lemeshow c-statistic showed no lack of fit (p=0.43). CONCLUSIONS: Neonatal mortality can be predicted for very preterm births based on the antenatal factors gestational age, antental corticosteroids, fetal gender, maternal age, ethnicity, presentation and level of hospital. This model can be helpful in antenatal counseling.

Ethnic disparities in perinatal mortality at 40 and 41 weeks of gestation.

OBJECTIVE: To evaluate whether maternal ethnicity affects perinatal mortality by week of gestation from 39 weeks onwards. STUDY DESIGN: In this cohort study, we used data from the nationwide Netherlands Perinatal Registry from 1999 until 2008. All singleton infants born between 39+0 and 42+6 weeks of gestation without congenital anomalies were included. We used crude and multivariate logistic regression analyses with white Europeans as the reference to calculate the adjusted odds ratios (aOR) of South Asian, African and Mediterranean women. The main outcome measure was perinatal mortality (antepartum and intrapartum/neonatal mortality within 7 days after birth). RESULTS: We studied 1,092,255 singleton deliveries. Perinatal mortality occurred in 2315 infants (2.1‰). There was interaction between gestational age and ethnicity (P<0.0001). In week 40 (40+0-40+6) South Asian (aOR 1.9; 95% CI 1.1-3.4) and Mediterranean (aOR 1.3; 95% CI 1.04-1.7) women had an increased risk of perinatal mortality. The perinatal mortality risk became greater in week 41 for South Asian (aOR 4.5 95% CI 2.8-7.2), African (aOR 2.2; 95%CI 1.4-3.4) and Mediterranean (aOR 2.2; 95% CI 1.8-2.9) women, especially among small for gestational age infants. CONCLUSION: With increasing gestational age beyond 39 weeks, perinatal mortality risk increases more strongly among South Asian, African and Mediterranean women compared to European whites.

Ethnic and racial disparities in the risk of preterm birth: a systematic review and meta-analysis.

OBJECTIVES: The aim of this study is to present a systematic review of available literature on the effect of maternal ethnicity (Africans/blacks, Asians, Hispanics, others) on the risk of preterm birth (PTB). STUDY DESIGN: Studies investigating ethnicity (or race) as a risk factor for PTB were included if performing adjustments for confounders. A meta-analysis was performed, and data were synthesized using a random effects model. RESULTS: Forty-five studies met the inclusion criteria. Black ethnicity was associated with an increased risk of PTB when compared with whites (range of adjusted odds ratios [ORs] 0.6 to 2.8, pooled OR 2.0; 95% confidence interval [CI] 1.8 to 2.2). For Asian ethnicity, there was no significant association (range of adjusted ORs 0.6 to 2.3). For Hispanic ethnicity, there also was no significant association (range of adjusted ORs 0.7 to 1.5). CONCLUSIONS: Ethnic disparities in the risk of PTB were clearly pronounced among black women. Future research should focus on preventative strategies for ethnic groups at high risk for PTB. Information on ethnic disparities in risk of PTB-related neonatal morbidity and mortality is lacking and is also a topic of interest for future research.

Ethnic disparities in the risk of adverse neonatal outcome after spontaneous preterm birth.

OBJECTIVE: To describe ethnic disparities in the risk of spontaneous preterm birth and related adverse neonatal outcome. DESIGN: Nationwide prospective cohort study. SETTING: The Netherlands, 1999-2007. POPULATION: Nine hundred and sixty-nine thousand, four hundred and ninety-one singleton pregnancies with a spontaneous onset of labor. METHODS: We investigated ethnic disparities in perinatal outcome for European white, African, South-Asian, Mediterranean and East-Asian women. We performed multivariate logistic regression analyses to calculate the adjusted odds ratio (aOR) and confidence intervals (CIs) of spontaneous preterm birth and the risk of subsequent neonatal morbidity and mortality. MAIN OUTCOME MEASURES: The primary outcome measure was spontaneous preterm birth before 37 completed weeks of gestation. Secondarily, we investigated subsequent adverse neonatal outcome, which was a composite outcome of intraventricular hemorrhage, bronchopulmonary dysplasia, infant respiratory distress syndrome, neonatal sepsis or neonatal mortality within 28 days after birth. RESULTS: Compared with European whites, the aOR of delivering preterm was 1.33 (95% CI 1.26-1.41) for African women, 1.58 (95% CI 1.47-1.69) for South-Asians, 0.88 (95% CI 0.84-0.91) for Mediterraneans and 1.04 (95% CI 0.98-1.11) for East-Asians. Subsequent odds of adverse neonatal outcome were significantly lower for African (aOR 0.51; 95% CI 0.41-0.64) and Mediterranean women (aOR 0.86; 95% CI 0.75-0.99) when compared with European whites. CONCLUSIONS: African and South-Asian women are at higher risk for preterm birth than European white women. However, the harmful effect of preterm birth on neonatal outcome is less severe for these women.

Recurrence risk of preterm birth in subsequent singleton pregnancy after preterm twin delivery.

OBJECTIVE: The purpose of this study was to investigate the recurrence risk of preterm birth (<37 weeks' gestation) in a subsequent singleton pregnancy after a previous nulliparous preterm twin delivery. STUDY DESIGN: We included 1957 women who delivered a twin gestation and a subsequent singleton pregnancy from the Netherlands Perinatal Registry. We compared the outcome of subsequent singleton pregnancy of women with a history of preterm delivery to the pregnancy outcome of women with a history of term twin delivery. RESULTS: Preterm birth in the twin pregnancy occurred in 1075 women (55%) vs 882 women (45%) who delivered at term. The risk of subsequent spontaneous singleton preterm birth was significantly higher after preterm twin delivery (5.2% vs 0.8%; odds ratio, 6.9; 95% confidence interval, 3.1-15.2). CONCLUSION: Women who deliver a twin pregnancy are at greater risk for delivering prematurely in a subsequent singleton pregnancy.

Development of a prognostic model for predicting spontaneous singleton preterm birth.

OBJECTIVE: To develop and validate a prognostic model for prediction of spontaneous preterm birth. STUDY DESIGN: Prospective cohort study using data of the nationwide perinatal registry in The Netherlands. We studied 1,524,058 singleton pregnancies between 1999 and 2007. We developed a multiple logistic regression model to estimate the risk of spontaneous preterm birth based on maternal and pregnancy characteristics. We used bootstrapping techniques to internally validate our model. Discrimination (AUC), accuracy (Brier score) and calibration (calibration graphs and Hosmer-Lemeshow C-statistic) were used to assess the model's predictive performance. Our primary outcome measure was spontaneous preterm birth at <37 completed weeks. RESULTS: Spontaneous preterm birth occurred in 57,796 (3.8%) pregnancies. The final model included 13 variables for predicting preterm birth. The predicted probabilities ranged from 0.01 to 0.71 (IQR 0.02-0.04). The model had an area under the receiver operator characteristic curve (AUC) of 0.63 (95% CI 0.63-0.63), the Brier score was 0.04 (95% CI 0.04-0.04) and the Hosmer Lemeshow C-statistic was significant (p<0.0001). The calibration graph showed overprediction at higher values of predicted probability. The positive predictive value was 26% (95% CI 20-33%) for the 0.4 probability cut-off point. CONCLUSIONS: The model's discrimination was fair and it had modest calibration. Previous preterm birth, drug abuse and vaginal bleeding in the first half of pregnancy were the most important predictors for spontaneous preterm birth. Although not applicable in clinical practice yet, this model is a next step towards early prediction of spontaneous preterm birth that enables caregivers to start preventive therapy in women at higher risk.

Reproductive outcome after early-onset pre-eclampsia.

BACKGROUND: Early-onset pre-eclampsia is an important cause of maternal and neonatal morbidity and mortality and is believed to have a significant impact on future maternal physical and psychological health. However, structured follow-up data of women with a history of early-onset pre-eclampsia are lacking. This study aims to present comprehensive data of a large cohort of women with a history of early-onset pre-eclampsia with respect to future reproductive health, family planning and subsequent pregnancy rates. METHODS: A tertiary referral cohort of 304 women entered the follow-up study at 6-12 months after their first delivery. Detailed data on maternal and neonatal outcomes, family planning and subsequent pregnancies were recorded. In addition, data on perspectives, major concerns and decision-making of women who had not achieved a second pregnancy were collected by questionnaire and structured interviews. Data were compared with a population of 268 low-risk primiparous women with an uncomplicated delivery. RESULTS: At a mean of 5.5 years after first delivery, 65.8% of women with a history of early-onset pre-eclampsia had achieved a second pregnancy compared with 77.6% of healthy controls. At follow-up, 19.1% of women with a history of early-onset pre-eclampsia had an active wish to become pregnant, whereas 15.1% of women did not wish to achieve a future pregnancy. In the latter group, decision-making was most commonly influenced by fear of recurrent disease (33%) and fear of delivering another premature child (33%) among others reasons, e.g. post-partum counseling and concerns of the partner. CONCLUSIONS: The majority of women with a history of early-onset pre-eclampsia achieve or wish to achieve a second pregnancy within a few years of their delivery. Nonetheless, first pregnancy early-onset pre-eclampsia appears to have a significant impact on future reproductive health and decision-making, emphasizing the importance of careful post-partum counseling.

Follow-up of prolapse surgery in rural Nepal.

Pelvic organ prolapse (POP) is a significant problem in Nepal. Surgical treatment is scarcely available and little is known of the results of POP surgery on women living under burdensome circumstances. The aim of our study was to set up a follow-up program in rural Nepal and evaluate POP surgery. In 2004 and 2006, 74 women with a POP from remote areas around Dhulikhel Hospital underwent prolapse surgery. Together with local contacts men, a plan was made to implement a follow-up program. All the operated patients were invited to a follow-up visit in March 2007. Thirty-three (45%) patients attended the follow-up: 85% (n = 28) found the effect of the procedure an improvement. A satisfactory anatomic outcome was found in 93% (n = 32). A remarkable finding was the reduction in physical labour after the surgical procedure in 50% of the follow-up cases. Some adjustments in the follow-up program may contribute to a higher participation.