Change in cervical length after arrested preterm labor and risk of preterm birth

OBJECTIVE

To assess the association between preterm birth and cervical length after arrested preterm labor in high-risk pregnant women.

METHODS

In this post-hoc analysis of a randomized clinical trial, transvaginal cervical length was measured in women whose contractions had ceased 48 h after admission for threatened preterm labor. At admission, women were defined as having a high risk of preterm birth based on a cervical length of < 15 mm or a cervical length of 15-30 mm with a positive fetal fibronectin test. Logistic regression analysis was used to investigate the association of cervical length measured at least 48 h after admission and of the change in cervical length between admission and at least 48 h later, with preterm birth before 34 weeks' gestation and delivery within 7 days after admission.

RESULTS

A total of 164 women were included in the analysis. Women whose cervical length increased between admission for threatened preterm labor and 48 h later (32%; n = 53) were found to have a lower risk of preterm birth before 34 weeks compared with women whose cervical length did not change (adjusted odds ratio (aOR), 0.24 (95% CI, 0.09-0.69)). The risk in women with a decrease in cervical length between the two timepoints was not different from that in women with no change in cervical length (aOR, 1.45 (95% CI, 0.62-3.41)). Moreover, greater absolute cervical length after 48 h was associated with a lower risk of preterm birth before 34 weeks (aOR, 0.90 (95% CI, 0.84-0.96)) and delivery within 7 days after admission (aOR, 0.91 (95% CI, 0.82-1.02)). Sensitivity analysis in women randomized to receive no intervention showed comparable results.

CONCLUSION

Our study suggests that the risk of preterm birth before 34 weeks is lower in women whose cervical length increases between admission for threatened preterm labor and at least 48 h later when contractions had ceased compared with women in whom cervical length does not change or decreases. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Induction of labor with Foley catheter and risk of subsequent preterm birth: follow-up study of two randomized controlled trials (PROBAAT-1 and -2)

OBJECTIVE

To evaluate the rate of preterm birth (PTB) in a subsequent pregnancy in women who had undergone term induction using a Foley catheter compared with prostaglandins.

METHODS

This was a follow-up study of two large randomized controlled trials (PROBAAT-1 and PROBAAT-2). In the original trials, women with a term singleton pregnancy with the fetus in cephalic presentation and with an indication for labor induction were randomized to receive either a 30-mL Foley catheter or prostaglandins (vaginal prostaglandin E2 in PROBAAT-1 and oral misoprostol in PROBAAT-2). Data on subsequent ongoing pregnancies > 16 weeks' gestation were collected from hospital charts from clinics participating in this follow-up study. The main outcome measure was preterm birth < 37 weeks' gestation in a subsequent pregnancy.

RESULTS

Fourteen hospitals agreed to participate in this follow-up study. Of the 1142 eligible women, 572 had been allocated to induction of labor using a Foley catheter and 570 to induction of labor using prostaglandins. Of these, 162 (14%) were lost to follow-up. In total, 251 and 258 women had a known subsequent pregnancy > 16 weeks' gestation in the Foley catheter and prostaglandin groups, respectively. There were no differences in baseline characteristics between the groups. The overall rate of PTB in a subsequent pregnancy was 9/251 (3.6%) in the Foley catheter group vs 10/258 (3.9%) in the prostaglandin group (relative risk (RR), 0.93; 95% CI, 0.38-2.24), and the rate of spontaneous PTB was 5/251 (2.0%) vs 5/258 (1.9%) (RR, 1.03; 95% CI, 0.30-3.51).

CONCLUSION

In women with term singleton pregnancy, induction of labor using a 30-mL Foley catheter is not associated with an increased risk of PTB in a subsequent pregnancy, as compared to induction of labor using prostaglandins. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Child outcomes after amnioinfusion compared with no intervention in women with second-trimester rupture of membranes: a long-term follow-up study of the PROMEXIL-III trial

OBJECTIVE

To assess the effect of transabdominal amnioinfusion or no intervention on long-term outcomes in children born after second-trimester prelabour rupture of the membranes (PROM between 16^+0/7 -24^+0/7  weeks) and oligohydramnios.

POPULATION

Follow up of infants of women who participated in the randomised controlled trial: PPROMEXIL-III (NTR3492).

METHODS

Surviving infants were invited for neurodevelopmental assessment up to 5 years of corrected age using a Bayley Scales of Infant and Toddler Development or a Wechsler Preschool and Primary Scale of Intelligence. Parents were asked to complete several questionnaires.

MAIN OUTCOME MEASURES

Neurodevelopmental outcomes were measured. Mild delay was defined as -1 standard deviation (SD), severe delay as -2 SD. Healthy long-term survival was defined as survival without neurodevelopmental delay or respiratory problems.

RESULTS

In the amnioinfusion group, 18/28 children (64%) died versus 21/28 (75%) in the no intervention group (relative risk 0.86; 95% confidence interval [CI] 0.60-1.22). Follow-up data were obtained from 14/17 (82%) children (10 amnioinfusion, 4 no intervention). In both groups, 2/28 (7.1%) had a mild neurodevelopmental delay. No severe delay was seen. Healthy long-term survival occurred in 5/28 children (17.9%) after amnioinfusion versus 2/28 (7.1%) after no intervention (odds ratio 2.50; 95% CI 0.53-11.83). When analysing data for all assessed survivors, 10/14 (71.4%) survived without mild neurodevelopmental delay and 7/14 (50%) were classified healthy long-term survivor.

CONCLUSIONS

In this small sample of women suffering second-trimester PROM and oligohydramnios, amnioinfusion did not improve long-term outcomes. Overall, 71% of survivors had no neurodevelopmental delay.

TWEETABLE ABSTRACT

Healthy long-term survival was comparable for children born after second-trimester PROM and treatment with amnioinfusion or no intervention.

Cost effectiveness of nifedipine compared with atosiban in the treatment of threatened preterm birth (APOSTEL III trial)

OBJECTIVE

To assess the cost-effectiveness of treatment with nifedipine compared with atosiban in women with threatened preterm birth.

DESIGN

An economic analysis alongside a randomised clinical trial (the APOSTEL III study).

SETTING

Obstetric departments of 12 tertiary hospitals and seven secondary hospitals in the Netherlands and Belgium.

POPULATION

Women with threatened preterm birth between 25 and 34 weeks of gestation, randomised for tocolysis with either nifedipine or atosiban.

METHODS

We performed an economic analysis from a societal perspective. We estimated costs from randomisation until discharge. Analyses for singleton and multiple pregnancies were performed separately. The robustness of our findings was evaluated in sensitivity analyses.

MAIN OUTCOME MEASURES

Mean costs and differences were calculated per woman treated with nifedipine or atosiban. Health outcomes were expressed as the prevalence of a composite of adverse perinatal outcomes.

RESULTS

Mean costs per patients were significantly lower in the nifedipine group [singleton pregnancies: €34,897 versus €43,376, mean difference (MD) -€8479 [95% confidence interval (CI) -€14,327 to -€2016)]; multiple pregnancies: €90,248 versus €102,292, MD -€12,044 (95% CI -€21,607 to € -1671). There was a non-significantly higher death rate in the nifedipine group. The difference in costs was mainly driven by a lower neonatal intensive care unit admission (NICU) rate in the nifedipine group.

CONCLUSION

Treatment with nifedipine in women with threatened preterm birth results in lower costs when compared with treatment with atosiban. However, the safety of nifedipine warrants further investigation.

TWEETABLE ABSTRACT

In women with threatened preterm birth, tocolysis using nifedipine results in lower costs when compared with atosiban.

Cost-effectiveness of diagnostic testing strategies including cervical-length measurement and fibronectin testing in women with symptoms of preterm labor

OBJECTIVE

To evaluate the cost-effectiveness of combining cervical-length (CL) measurement and fetal fibronectin (fFN) testing in women with symptoms of preterm labor between 24 and 34 weeks' gestation.

METHODS

This was a model-based cost-effectiveness analysis evaluating seven test-treatment strategies based on CL measurement and/or fFN testing in women with symptoms of preterm labor from a societal perspective, in which neonatal outcomes and costs were weighted. Estimates of disease prevalence, test accuracy and costs were based on two recently performed nationwide cohort studies in The Netherlands.

RESULTS

Strategies using fFN testing and CL measurement separately to predict preterm delivery are associated with higher costs and incidence of adverse neonatal outcomes compared with strategies that combine both tests. Additional fFN testing when CL is 15-30 mm was considered cost effective, leading to a cost saving of €3919 per woman when compared with a treat-all strategy, with a small deterioration in neonatal health outcomes, namely one additional perinatal death and 21 adverse outcomes per 10 000 women with signs of preterm labor (incremental cost-effectiveness ratios €39 million and €1.9 million, respectively). Implementing this strategy in The Netherlands, a country with about 180 000 deliveries annually, could lead to an annual cost saving of between €2.4 million and €7.6 million, with only a small deterioration in neonatal health outcomes.

CONCLUSION

In women with symptoms of preterm labor at 24-34 weeks' gestation, performing additional fFN testing when CL is between 15 and 30 mm is a viable and cost-saving strategy. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Prenatal (non)treatment decisions in extreme prematurity: evaluation of Decisional Conflict and Regret among parents

OBJECTIVE

To evaluate Decisional Conflict and Regret among parents regarding the decision on initiating comfort or active care in extreme prematurity and to relate these to decision-making characteristics.

STUDY DESIGN

A nationwide, multicenter, cross-sectional study using an online survey in the Netherlands. Data were collected from March 2015 to March 2016 among all parents with infants born at 24^+0/7-24^+6/7 weeks gestational age in 2010-2013. The survey contained a Decisional Conflict and Decision Regret Scale (potential scores range from 0 to 100) and decision-making characteristics.

RESULTS

Sixty-one surveys were returned (response rate 27%). The median Decisional Conflict score was 28. From the subscores within Decisional Conflict, 'values clarity' revealed the highest median score of 42-revealing that parents felt unclear about personal values for benefits and risks of the decision on either comfort care or active care. The median Decision Regret score was 0. Regret scores were influenced by the actual decision made and by outcome: Decision Regret was lower in the active care group and in the survivor group.

CONCLUSION

We found little Decisional Conflict and no Decision Regret among parents regarding decision-making at 24 weeks gestation.

Prediction of Time to Delivery Week-by-Week in Women with a Triplet Pregnancy

Objective Some clinicians advise prophylactic administration of antenatal steroids for fetal lung maturation in women with a triplet pregnancy. However, the effect of corticosteroids is limited to 10 to 14 days after administration. The aim of this study was to assess the natural course of triplet pregnancies to allow a better anticipation for administration of corticosteroids. Study Design We collected data on all triplet pregnancies in the Netherlands from 1999 to 2007 from the Netherlands Perinatal Registration. We calculated time to delivery, the risk of delivery in 2-week intervals at different gestational ages, and the time frame between hospital admission and delivery of the first child. Results Median gestational age at delivery of 494 women with a triplet pregnancy was 33⁺⁴ weeks (interquartile range of 31-35⁺¹ weeks). Twenty-one women (4.3%) delivered between 22 and 24 weeks and 146 women (29.6%) delivered before 32 weeks. At a gestational age of 24 weeks, the chance to deliver within the next week was 0.6%. For 26, 28, 30, 31, and 32 weeks, these risks were 2.4, 2.5, 8.1, 7, and 16.7%, respectively. Conclusion Before 32 weeks of gestation, prophylactic administration of steroids is not indicated as the risk to deliver within 7 days is < 10%.

A multivariable model to guide the decision for pessary placement to prevent preterm birth in women with a multiple pregnancy: a secondary analysis of the ProTWIN trial

OBJECTIVE

The ProTWIN Trial (NTR1858) showed that, in women with a multiple pregnancy and a cervical length < 25(th) percentile (38 mm), prophylactic use of a cervical pessary reduced the risk of adverse perinatal outcome. We investigated whether other maternal or pregnancy characteristics collected at baseline can improve identification of women most likely to benefit from pessary placement.

METHODS

ProTWIN is a multicenter randomized trial in which 808 women with a multiple pregnancy were assigned to pessary or control. Using these data we developed a multivariable logistic model comprising treatment, cervical length, chorionicity, pregnancy history and number of fetuses, and the interaction of these variables with treatment as predictors of adverse perinatal outcome.

RESULTS

Short cervix, monochorionicity and nulliparity were predictive factors for a benefit from pessary insertion. History of previous preterm birth and triplet pregnancy were predictive factors of possible harm from pessary. The model identified 35% of women as benefiting (95% CI, 32-39%), which is 10% more than using cervical length only (25%) for pessary decisions. The model had acceptable calibration. We estimated that using the model to guide the choice of pessary placement would reduce the risk of adverse perinatal outcome significantly from 13.5% when no pessary is inserted to 8.1% (absolute risk reduction, 5.4% (95% CI, 2.1-8.6%)).

CONCLUSIONS

We developed and internally validated a multivariable treatment selection model, with cervical length, chorionicity, pregnancy history and number of fetuses. If externally validated, it could be used to identify women with a twin pregnancy who would benefit from a pessary, and lead to a reduction in adverse perinatal outcomes in these women. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Vaginal birth after a caesarean section: the development of a Western European population-based prediction model for deliveries at term

OBJECTIVE

To develop and internally validate a model that predicts the outcome of an intended vaginal birth after caesarean (VBAC) for a Western European population that can be used to personalise counselling for deliveries at term.

DESIGN

Registration-based retrospective cohort study.

SETTING

Five university teaching hospitals, seven non-university teaching hospitals, and five non-university non-teaching hospitals in the Netherlands.

POPULATION

A cohort of 515 women with a history of one caesarean section and a viable singleton pregnancy, without a contraindication for intended VBAC, who delivered at term.

METHODS

Potential predictors for a vaginal delivery after caesarean section were chosen based on literature and expert opinions. We internally validated the prediction model using bootstrapping techniques.

MAIN OUTCOME MEASURES

Predictors for VBAC. For model validation, the area under the receiver operating characteristic curve (AUC) for discriminative capacity and calibration-per-risk-quantile for accuracy were calculated.

RESULTS

A total of 371 out of 515 women had a VBAC (72%). Variables included in the model were: estimated fetal weight greater than the 90(th) percentile in the third trimester; previous non-progressive labour; previous vaginal delivery; induction of labour; pre-pregnancy body mass index; and ethnicity. The AUC was 71% (95% confidence interval, 95% CI = 69-73%), indicating a good discriminative ability. The calibration plot shows that the predicted probabilities are well calibrated, especially from 65% up, which accounts for 77% of the total study population.

CONCLUSION

We developed an appropriate Western European population-based prediction model that is aimed to personalise counselling for term deliveries.