Randomized controlled trial of induction at 38 weeks versus 40 weeks gestation on maternal and infant outcomes in women with insulin-controlled gestational diabetes

Predictive Factors for Successful Cervical Ripening among Women with Gestational Diabetes Mellitus at Term: A Prospective Study

The purpose of this prospective cohort study is to identify the predictive factors for vaginal delivery among women (n = 146) who underwent cervical ripening using a dinoprostone insert (PG) alone (13.7%), cervical ripening balloon (CRB) alone (52.7%), oral misoprostol (M) alone (4.1%), or repeated methods (R, 29.5%) for gestational diabetes mellitus (GDM) at term, and to analyze maternal and neonatal morbidity outcomes according to the method for cervical ripening. After cervical ripening, vaginal delivery occurred in 84.2% (n = 123) and was similar among groups (90.0% after PG, 83.1% after CRB, 83.3% after M, and 83.7% after R; p = 0.89). After a multivariable logistic regression analysis adjusted for potential confounders, the internal cervical os being open before cervical ripening was a predictor of vaginal delivery (adjusted odds ratio (OR) of 4.38, 95% confidence index (CI) of 1.62-13.3, p = 0.03), and previous cesarean delivery was a predictor of cesarean delivery (aOR of 7.67, 95% CI of 2.49-24.00, p < 0.01). Birthweight was also significantly associated with cesarean delivery (aOR of 1.15, 95% CI of 1.03-1.31, p = 0.02). The rates of maternal and neonatal morbidity outcomes were 10.9% (n = 16) and 19.9% (n = 29), respectively, and did not differ according to the mode of delivery and to the method used for cervical ripening. Identifying these specific high-risk women (previous cesarean delivery and internal cervical os being closed before cervical ripening) for cesarean delivery among women who underwent cervical ripening for GDM at term is important and practical for all physicians to make a decision in partnership with women.

Gestational Age of Delivery in Pregnancies Complicated by Diabetes

Background: The recommended gestational age to deliver pregnancies complicated by diabetes ranges from 34 to 39 weeks of gestation. The objective of this study was to determine the optimal gestational age for delivery of patients with diabetes to minimize perinatal death. Methods: We extracted a population-based cohort of singleton, nonanomalous infants of diabetic pregnancies from the Missouri birth registry for the period January 1, 1989 to December 31, 2005 and compared perinatal outcomes of planned deliveries at 37, 38, 39, and 40 weeks to expectant management. Planned deliveries were identified by induction or cesarean delivery without documented medical or obstetric indications. The primary outcome was perinatal death, defined as stillbirth or neonatal death within 28 days of birth. Secondary outcomes were independent stillbirth, independent neonatal death, and a composite adverse neonatal event of assisted ventilation >30 minutes, birth injury, seizures, or 5-minute Apgar score ≤3. Groups were compared using t test and chi-square as appropriate. Results: In 4,905 diabetic pregnancies reaching 37 weeks, 1,012 (20.6%) patients were insulin dependent. Overall, the risk of perinatal death at any gestational age examined was low (3/1,000 births or lower), as was the risk of the adverse perinatal outcome (<2%). When only patients who were insulin dependent were included in the analysis, the risk of perinatal death at any gestational age remained low at 6 per 1,000 births or fewer. Conclusion: Delivery as early as 37 weeks is reasonable for women who have diabetes, although the absolute risk of perinatal death is low at 37 to 39 weeks.

Timing of delivery in women with diabetes: A population-based study

INTRODUCTION

Women with diabetes, and their infants, have an increased risk of adverse events due to excess fetal growth. Earlier delivery, when fetuses are smaller, may reduce these risks. This study aimed to evaluate the week-specific risks of maternal and neonatal morbidity/mortality to assist with obstetrical decision making.

MATERIAL AND METHODS

In this population-based cohort study, women with type 1 diabetes (n = 5889), type 2 diabetes (n = 9422) and gestational diabetes (n = 138 917) and a comparison group without diabetes (n = 2 553 243) who delivered a singleton infant at ≥36 completed weeks of gestation between 2004 and 2014 were identified from the Canadian Institute of Health Information Discharge Abstract Database. Multivariate logistic regression was used to determine the week-specific rates of severe maternal and neonatal morbidity/mortality among women delivered iatrogenically vs those undergoing expectant management.

RESULTS

For all women, the absolute risk of severe maternal morbidity/mortality was low, typically impacting less than 1% of women, and there was no significant difference in gestational age-specific severe maternal morbidity/mortality between iatrogenic delivery and expectant management among women with any form of diabetes. Among women with gestational diabetes, iatrogenic delivery was associated with an increased risk of neonatal morbidity/mortality compared with expectant management at 36 and 37 weeks' gestation (76.7 and 27.8 excess cases per 1000 deliveries, respectively) and a lower risk of neonatal morbidity/mortality at 38, 39 and 40 weeks' gestation (7.9, 27.3 and 15.9 fewer cases per 1000 deliveries, respectively). Increased risks of severe neonatal morbidity following iatrogenic delivery compared with expectant management were also observed for women with type 1 diabetes at 36 (98.3 excess cases per 1000 deliveries) and 37 weeks' gestation (44.5 excess cases per 1000 deliveries) and for women with type 2 diabetes at 36 weeks' gestation (77.9 excess cases per 1000 deliveries) weeks.

CONCLUSIONS

The clinical decision regarding timing of delivery is complex and contingent on maternal-fetal wellbeing, including adequate glycemic control. This study suggests that delivery at 38, 39 or 40 weeks' gestation may optimize neonatal outcomes among women with diabetes.

Planned birth at or near term for improving health outcomes for pregnant women with pre-existing diabetes and their infants

BACKGROUND

Pregnant women with pre-existing diabetes (Type 1 or Type 2) have increased rates of adverse maternal and neonatal outcomes. Current clinical guidelines support elective birth, at or near term, because of increased perinatal mortality during the third trimester of pregnancy.This review replaces a review previously published in 2001 that included "diabetic pregnant women", which has now been split into two reviews. This current review focuses on pregnant women with pre-existing diabetes (Type 1 or Type 2) and a sister review focuses on women with gestational diabetes.

OBJECTIVES

To assess the effect of planned birth (either by induction of labour or caesarean birth) at or near term gestation (37 to 40 weeks' gestation) compared with an expectant approach, for improving health outcomes for pregnant women with pre-existing diabetes and their infants. The primary outcomes relate to maternal and perinatal mortality and morbidity.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (15 August 2017), and reference lists of retrieved studies.

SELECTION CRITERIA

We planned to include randomised trials (including those using a cluster-randomised design) and non-randomised trials (e.g. quasi-randomised trials using alternate allocation) which compared planned birth, at or near term, with an expectant approach for pregnant women with pre-existing diabetes.

DATA COLLECTION AND ANALYSIS

Two of the review authors independently assessed study eligibility. In future updates of this review, at least two of the review authors will extract data and assess the risk of bias in included studies. We will also assess the quality of the evidence using the GRADE approach.

MAIN RESULTS

We identified no eligible published trials for inclusion in this review.We did identify one randomised trial which examined whether expectant management reduced the incidence of caesarean birth in uncomplicated pregnancies of women with gestational diabetes (requiring insulin) and with pre-existing diabetes. However, published data from this trial does not differentiate between pre-existing and gestational diabetes, and therefore we excluded this trial.

AUTHORS' CONCLUSIONS

In the absence of evidence, we are unable to reach any conclusions about the health outcomes associated with planned birth, at or near term, compared with an expectant approach for pregnant women with pre-existing diabetes.This review demonstrates the urgent need for high-quality trials evaluating the effectiveness of planned birth at or near term gestation for pregnant women with pre-existing (Type 1 or Type 2) diabetes compared with an expectant approach.

Planned birth at or near term for improving health outcomes for pregnant women with gestational diabetes and their infants

BACKGROUND

Gestational diabetes is a type of diabetes that occurs during pregnancy. Women with gestational diabetes are more likely to experience adverse health outcomes such as pre-eclampsia or polyhydramnios (excess amniotic fluid). Their babies are also more likely to have health complications such as macrosomia (birthweight > 4000 g) and being large-for-gestational age (birthweight above the 90th percentile for gestational age). Current clinical guidelines support elective birth, at or near term in women with gestational diabetes to minimise perinatal complications, especially those related to macrosomia.This review replaces a review previously published in 2001 that included "diabetic pregnant women", which has now been split into two reviews. This current review focuses on pregnant women with gestational diabetes and a sister review focuses on women with pre-existing diabetes (Type 1 or Type 2).

OBJECTIVES

To assess the effect of planned birth (either by induction of labour or caesarean birth), at or near term (37 to 40 weeks' gestation) compared with an expectant approach for improving health outcomes for women with gestational diabetes and their infants. The primary outcomes relate to maternal and perinatal mortality and morbidity.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) (15 August 2017), and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised trials comparing planned birth, at or near term (37 to 40 weeks' gestation), with an expectant approach, for women with gestational diabetes. Cluster-randomised and non-randomised trials (e.g. quasi-randomised trials using alternate allocation) were also eligible for inclusion but none were identified.

DATA COLLECTION AND ANALYSIS

Two of the review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included study. The quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

The findings of this review are based on a single trial involving 425 women with gestational diabetes. The trial compared induction of labour with expectant management (waiting for the spontaneous onset of labour in the absence of any maternal or fetal issues that may necessitate birth) in pregnant women with gestational diabetes at term. We assessed the overall risk of bias as being low for most domains, apart from performance, detection and attrition bias (for outcome perineum intact), which we assessed as being at high risk. It was an open-label trial, and women and healthcare professionals were not blinded.There were no clear differences between women randomised to induction of labour and women randomised to expectant management for maternal mortality or serious maternal morbidity (risk ratio (RR) 1.48, 95% confidence interval (CI) 0.25 to 8.76, one trial, 425 women); caesarean section (RR 1.06, 95% CI 0.64 to 1.77, one trial, 425 women); or instrumental vaginal birth (RR 0.81, 95% CI 0.45 to 1.46, one trial, 425 women). For the primary outcome of maternal mortality or serious maternal morbidity, there were no deaths in either group and serious maternal morbidity related to admissions to intensive care unit. The quality of the evidence contributing to these outcomes was assessed as very low, mainly due to the study having high risk of bias for some domains and because of the imprecision of effect estimates.In relation to primary neonatal outcomes, there were no perinatal deaths in either group. The quality of evidence for this outcome was judged as very low, mainly due to high risk of bias and imprecision of effect estimates. There were no clear differences in infant outcomes between women randomised to induction of labour and women randomised to expectant management: shoulder dystocia (RR 2.96, 95% CI 0.31 to 28.21, one trial, 425 infants, very low-quality evidence); large-for-gestational age (RR 0.53, 95% CI 0.28 to 1.02, one trial, 425 infants, low-quality evidence).There were no clear differences between women randomised to induction of labour and women randomised to expectant management for postpartum haemorrhage (RR 1.17, 95% CI 0.53 to 2.54, one trial, 425 women); admission to intensive care unit (RR 1.48, 95% CI 0.25 to 8.76, one trial, 425 women); and intact perineum (RR 1.02, 95% CI 0.73 to 1.43, one trial, 425 women). No infant experienced a birth trauma, therefore, we could not draw conclusions about the effect of the intervention on the outcomes of brachial plexus injury and bone fracture at birth. Infants of women in the induction-of-labour group had higher incidences of neonatal hyperbilirubinaemia (jaundice) when compared to infants of women in the expectant-management group (RR 2.46, 95% CI 1.11 to 5.46, one trial, 425 women).We found no data on the following prespecified outcomes of this review: postnatal depression, maternal satisfaction, length of postnatal stay (mother), acidaemia, intracranial haemorrhage, hypoxia ischaemic encephalopathy, small-for-gestational age, length of postnatal stay (baby) and cost.The authors of this trial acknowledge that it is underpowered for their primary outcome of caesarean section. The authors of the trial and of this review note that the CIs demonstrate a wide range, therefore making it inappropriate to draw definite conclusions.

AUTHORS' CONCLUSIONS

There is limited evidence to inform implications for practice. The available data are not of high quality and lack power to detect possible important differences in either benefit or harm. There is an urgent need for high-quality trials evaluating the effectiveness of planned birth at or near term gestation for women with gestational diabetes compared with an expectant approach.