The risk of stillbirth and infant death by each additional week of expectant management stratified by maternal age

Unplanned cesarean sections in advanced maternal age: A predictive model

INTRODUCTION

As maternal age during pregnancy is rising all over the world, there is a growing need for prognostic factors that determine maternal and perinatal outcomes in older women.

MATERIAL AND METHODS

This study is a retrospective cohort study of women aged 40 years or older at the time of delivery in four Santeon hospitals across the Netherlands between January 2016 and December 2019. Outcomes were compared between women of 40-44 years (advanced maternal age) and 45 years and older (very advanced maternal age). Primary outcome was unplanned cesarean section, secondary outcomes included postpartum hemorrhage and neonatal outcomes. Multivariate regression analysis was performed to analyze predictive factors for unplanned cesarean sections in women who attempted vaginal delivery. Subsequently, a predictive model and risk scores were constructed to predict unplanned cesarean section.

RESULTS

A cohort of 1660 women was analyzed; mean maternal age was 41.4 years, 4.8% of the women were 45 years and older. In both groups, more than half of the women had not delivered vaginally before. Unplanned cesarean sections were performed in 21.1% of the deliveries in advanced maternal age and in 29.1% in very advanced maternal age. Four predictive factors were significantly correlated with unplanned cesarean sections: higher body mass index (BMI), no previous vaginal delivery, spontaneous start of delivery and number of days needed for cervical priming. A predictive model was constructed from these factors with an area under the curve of 0.75 (95% confidence interval 0.72-0.78). A sensitivity analysis in nulliparous women proved that BMI, days of cervical priming, age, and gestational age were risk factors, whereas spontaneous start of delivery and induction were protective factors. There was one occurrence of neonatal death.

CONCLUSIONS

Women of advanced maternal age and those of very advanced maternal age have a higher chance of having an unplanned cesarean section compared to the general obstetric population in the Netherlands. Unplanned cesarean sections can be predicted through use of our predictive model. Risk increases with higher BMI, no previous vaginal delivery, and increasing number of days needed for cervical priming, whereas spontaneous start of labor lowers the risk. In nulliparous women, age and gestational age also increase risk, but induction lowers the risk of having an unplanned cesarean section.

The influence of timing of oocytes retrieval and embryo transfer on the IVF-ET outcomes in patients having bilateral salpingectomy due to bilateral hydrosalpinx

Objective

The objective of the study was to investigate whether the sequence of oocyte retrieval and salpingectomy for hydrosalpinx affects pregnancy outcomes of in vitro fertilization and embryo transfer (IVF-ET) patients.

Study Design

There were 1,610 bilateral hydrosalpinx patients who underwent laparoscopy salpingectomy and IVF-ET/intracytoplasmic sperm injection (ICSI) from January 2009 to December 2018. They were divided into two groups: oocyte retrieval first group: 235 accepted oocyte retrieval before salpingectomy; operation first group: 1,375 accepted oocyte retrieval after salpingectomy. The basic information and pregnancy outcomes of the two groups were compared. The pregnancy outcomes and influencing factors were analyzed among patients at different starting times of frozen-thawed embryo transfer (FET) or oocyte retrieval after the salpingectomy.

Results

Patients in the oocyte retrieval first group had higher levels of basal follicle stimulating hormone and lower anti-Mullerian hormone levels (P < 0.05). There were no cases of pelvic infection or oocyte and embryo contamination after oocyte retrieval in the oocyte retrieval first group. In the frozen cycle, the clinical pregnancy and miscarriage rates of the oocyte retrieval first group were lower than those in the operation first group (P < 0.05), while the live birth rate was not significantly different (P > 0.05). The live birth rates of patients ≥35 years old in the operation first group and the oocyte retrieval first group were not significantly different (29.3% vs. 23.3%, P = 0.240). After adjusting for age and antral follicle count (AFC), oocyte retrieval 4-6 and 7-12 months after the operation had higher accumulated pregnancy rates [OR 1.439 (1.045-1.982), P = 0.026; OR 1.509 (1.055-2.158), P = 0.024] and higher accumulated live birth rates [OR 1.419 (1.018-1.977), P = 0.039; OR 1.544 (1.068-2.230), P = 0.021]. No significant difference was observed in the pregnancy outcomes of frozen embryo transfer at different times after salpingectomy (P > 0.05).

Conclusion

No contamination of the embryo or infection was observed in patients who underwent oocyte retrieval before the operation. The interval between the operation and frozen embryo transfer did not affect the pregnancy outcomes. After adjusting for age and AFC, patients who underwent oocyte retrieval 4-6 and 7-12 months after the operation had higher accumulated pregnancy rates and live birth rates.

Changes in obstetrical practices and pregnancy outcomes following the ARRIVE trial

BACKGROUND

The ARRIVE trial demonstrated the benefit of induction of labor at 39 weeks gestation. Obstetrics departments across the United States faced the challenge of adapting clinical practice in light of these data while managing logistical constraints.

OBJECTIVE

To determine if there were changes in obstetrical practices and perinatal outcomes in the United States after the ARRIVE trial publication.

STUDY DESIGN

This was a population-based retrospective cohort study of low-risk, nulliparous women who initiated prenatal care by 12 weeks gestation with singleton, nonanomalous pregnancies delivering at ≥39 weeks. Data were obtained from the US Natality database. The pre-ARRIVE group were women who delivered between January 1, 2015 and December 31, 2017. The post-ARRIVE group consisted of women who delivered between January 1, 2019 and December 31, 2019. Births that occurred in 2018 were excluded. Practice outcomes were rates of induction of labor, timing of delivery, and cesarean delivery rate. Adverse maternal outcomes were blood transfusion and admission to medical intensive care unit. Adverse neonatal outcomes were need for assisted ventilation (immediate and >6 hours), 5-minute APGAR score <3, neonatal intensive care unit admission, seizures, and surfactant use. Univariate and multivariate analyses were performed. Trends were tested across the time period represented by the pre-ARRIVE group using Cochran-Armitage trend test.

RESULTS

There were 1,966,870 births in the pre-ARRIVE group and 609,322 in the post-ARRIVE group. The groups differed in age, race, body mass index, marital status, infertility treatment, and smoking history (P<.001). After adjusting for these differences, the post-ARRIVE group was more likely to undergo induction (36.1% vs 30.2%; adjusted odds ratio, 1.36 [1.36-1.37]) and deliver by 39+6 weeks of pregnancy (42.8% vs 39.9%; adjusted odds ratio, 1.14 [1.14-1.15]). The post-ARRIVE group had a significantly lower rate of cesarean delivery than the pre-ARRIVE group (27.3 % vs 27.9%; adjusted odds ratio, 0.94 [0.93-0.94]). Patients in the post-ARRIVE group were more likely to receive a blood transfusion (0.4% vs 0.3%; adjusted odds ratio, 1.43 [1.36-1.50]) and be admitted to medical intensive care unit (0.09% vs 0.08%; adjusted odds ratio, 1.20 [1.09-1.33]). Neonates in the post-ARRIVE group were more likely to need assisted ventilation at birth (3.5% vs 2.8%; adjusted odds ratio, 1.28 [1.26-1.30]) and >6 hours (0.6% vs 0.5%; adjusted odds ratio, 1.36 [1.31-1.41]). The neonates in the post-ARRIVE group were more likely to have low 5-minute APGAR scores (0.4% vs 0.3%; adjusted odds ratio, 0.91 [0.86-0.95]). Neonatal intensive care unit admission did not differ between the 2 groups (4.9% vs 4.9%; adjusted odds ratio, 1.01 [0.99-1.03]). There were no differences in neonatal seizures (0.04% vs 0.04%; adjusted odds ratio, 0.97 [0.84-1.13]), and surfactant use (0.08% vs 0.07%; adjusted odds ratio, 1.05 [0.94-1.17]) between the 2 groups.

CONCLUSION

There were more inductions of labor, more deliveries at 39 weeks' gestation, and fewer cesarean deliveries in the year after the ARRIVE trial publication. The small but statistically significant increase in some adverse maternal and neonatal outcomes should be explored to determine if they are related with concurrent changes in obstetrical practices.

Measuring severe neonatal morbidity using hospital discharge data in France

BACKGROUND

Measuring infant health at birth is key for surveillance and research in obstetrics and neonatology, but there is no international consensus on morbidity indicators. The Neonatal Adverse Outcome Indicator (NAOI) is a composite indicator, developed in Australia, which measures the burden of severe neonatal morbidity using hospital discharge data.

OBJECTIVE

To evaluate the applicability of the NAOI in France for surveillance and research.

METHODS

We constituted a cohort of live births ≥24 weeks' gestational age in Metropolitan France from 2014 to 2015 using hospital discharge, insurance claims and cause of death data. Outlier hospitals were identified using funnel plots of standardised morbidity ratios (SMR), and their coding patterns were assessed. We compared the NAOI and its component codes with published Australian and English data and estimated unadjusted and adjusted risk ratios for known risk factors for neonatal morbidity.

RESULTS

We included 1,459,123 births (511 hospitals). Twenty-eight hospitals had SMR above funnel plot control limits. Newborns with NAOI morbidities in these hospitals had lower mortality and shorter stays than in other hospitals. Amongst within-limit hospitals, NAOI prevalence was 4.8%, comparable to Australia (4.6%) and England (5.4%). Most individual components had a similar prevalence, with the exception of respiratory support, intravenous fluid procedures and infection. NAOI was lowest at 39 weeks (2.2%) with higher risks for maternal age ≥40 (relative risk [RR] 1.47, 95% confidence interval [CI] 1.42, 1.51), state medical insurance (RR 1.60, 95% CI 1.52, 1.68), male sex (RR 1.21, 95% CI 1.19, 1.23) and birthweight <3^rd percentile (RR 4.60, 95% CI 4.51, 4.69).

CONCLUSIONS

The NAOI provides valuable information on population prevalence of severe neonatal morbidity and its risk factors. Whilst the prevalence was similar in high-income countries with comparable neonatal mortality levels, ensuring valid comparisons between countries and hospitals will require further work to harmonize coding procedures, especially for infection and respiratory morbidity.

Stillbirth or neonatal death before 45 post-menstrual weeks in relation to gestational duration in pregnancies at 39 weeks of gestation or beyond: the impact of parity and body mass index. A national cohort study

OBJECTIVE

To investigate the risk of stillbirth or neonatal death before 45 post-menstrual weeks in relation to gestational duration, stratified by body mass index (BMI) and parity.

DESIGN

Retrospective study.

SETTING

Data from the Swedish Medical Birth Register.

POPULATION

Singleton, cephalic births at between 39⁺⁰ and 42⁺²  weeks of gestation, 2005-2016 (n = 892 339).

METHODS

Relative risk ratios for mortality in relation to gestational duration were stratified by parity and BMI, and were adjusted for maternal age, smoking, country of birth and educational level.

MAIN OUTCOME MEASURES

Primary outcome: stillbirth or neonatal death before 45 post-menstrual weeks. Secondary outcome: stillbirth.

RESULTS

Among children of primiparous women, children born at 41⁺³  weeks of gestation, or later, were at increased risk of stillbirth or neonatal death before 45 post-menstrual weeks compared with children born between 39⁺⁰ and 40⁺²  weeks of gestation (aRR 1.29, 95% CI 1.10-1.52). For primiparous women with BMIs of <25, 25-29.9 and ≥ 30 kg/m² , the corresponding aRRs were: 1.04 (95% CI 0.81-1.34), 1.25 (95% CI 0.94-1.66) and 1.52 (95% CI 1.10-2.10), respectively. No significant increase in risk with gestational age was detected for multiparous women, regardless of BMI class. Among primipara, the risk of stillbirth increased with gestational duration in all BMI classes, with the highest risk increase for BMI ≥ 30 kg/m² , from 0.8/1000 at 40⁺³ -40⁺⁶  weeks of gestation to 4.0/1000 at 42⁺⁰ -42⁺²  weeks of gestation.

CONCLUSIONS

At 41⁺³ -42⁺²  weeks of gestation, pregnancy duration was associated with an increased risk for stillbirth or neonatal death before 45 post-menstrual weeks among primiparous women, especially among women who were obese. For multiparous women, no significant association between gestational duration and mortality was found.

TWEETABLE ABSTRACT

In term pregnancies the risk for stillbirth and neonatal death is affected by gestational age, parity and BMI.

Australia's persistently high rate of early-term prelabour Caesarean delivery

Objective To compare the incidence of prelabour Caesarean delivery (PCD) at early term (37 weeks and 0 days (370) to 38 weeks and 6 days (386) of gestation) between Australian states and hospital sectors over time and to compare these rates with those of England and the United States of America (USA). Method A population-based descriptive study of 556040 singleton PCDs at term (370-406 weeks) in all public and private hospitals in Australian states, 2005-16, was performed. The primary outcome was the early-term PCD rate, defined as early-term PCDs as a percentage of all term PCDs. Results Across Australian states, the early-term PCD rate fell from 56.4% in 2005 to 52.0% in 2016. Over a similar period, England's rate fell from 48.2% in 2006-07 to 35.2% in 2016-17, while the USA's rate fell from 47.4% in 2006 to 34.2% in 2016. Australian public hospitals reduced their rate from 54.2% in 2005 to 44.7% in 2016, but the rate increased in private hospitals from 59.1% in 2005 to 62.5% in 2016. There was considerable variation between states and hospital sectors. Conclusions The early-term PCD rate increased in Australian private hospitals from 2005 to 2016. The public hospital rate fell by nearly 10% over the period but remained ~10% above the English and USA national rates. What is known about the topic? Babies born at early term (370-386 weeks) are at greater risk of morbidity than babies born at full term (390-406 weeks). Australia has a persistently high rate of early-term prelabour Caesarean delivery (PCD). What does this paper add? This paper reveals concerning differences in the early-term PCD rate between Australian states and hospital sectors. Further, the paper highlights that both Australian hospital sectors (public and private) have not reduced their rates to levels achieved in England and the USA. What are the implications for practitioners? These results should inform efforts to reduce Australia's early-term PCD rate to prevent harm to babies.

Adverse Outcomes among Low-Risk Pregnancies at 39 to 41 Weeks: Stratified by Birth Weight Percentile

OBJECTIVE

This study aimed to assess the risk of adverse outcomes among low-risk pregnancies at 39 to 41 weeks, stratified by birth weight percentile.

STUDY DESIGN

This retrospective cohort study utilized the U.S. vital statistics datasets (2013-2017) and evaluated low-risk women with nonanomalous cephalic singleton gestations who labored and delivered at 39 to 41 weeks, regardless of ultimate mode of delivery. Newborns were categorized as small (<10th percentile), large (>90th percentile), or appropriate (10-90th percentile) for gestational ages (SGA, LGA, and AGA, respectively). The primary outcome, composite neonatal adverse outcome (CNAO), included Apgar's score <5 at 5 minutes, assisted ventilation >6 hours, seizure, or neonatal death. The secondary outcome, composite maternal adverse outcome (CMAO), included intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy. Multivariable Poisson's regression was used to estimate the association (using adjusted relative risk [aRR] and 95% confidence interval [CI]).

RESULTS

Of 19.8 million live births during the study interval, approximately 8.9 million (44.9%) met the inclusion criteria, with 9.9% being SGA, 9.2% being LGA, and 80.9% being AGA. SGA newborns delivered at 40 (aRR = 1.17; 95% CI: 1.12-1.23) and at 41 weeks (aRR = 1.55; 95% CI: 1.45-1.66) had a higher risk of CNAO than at 39 weeks. Similarly, LGA newborns delivered at 40 (aRR = 1.13; 95% CI: 1.07-1.19) and 41 weeks (aRR = 1.44; 95% CI: 1.35-1.54) and AGA newborns delivered at 40 (aRR = 1.24; 95% CI: 1.21-1.26) and 41 weeks (aRR = 1.57; 95% CI: 1.53-1.61) also had a higher risk of CNAO than at 39 weeks. CMAO was also significantly higher at 40 and 41 weeks than at 39 weeks, regardless of whether the mothers delivered SGA, LGA, or AGA newborns.

CONCLUSION

Among low-risk pregnancies, the risks of composite neonatal and maternal adverse outcomes increase from 39 through 41 weeks' gestation, irrespective of whether newborns are SGA, LGA, or AGA.

Neonatal and Maternal Composite Adverse Outcomes Among Low-Risk Nulliparous Women Compared With Multiparous Women at 39-41 Weeks of Gestation

OBJECTIVE

To estimate whether the frequency of adverse maternal and neonatal outcomes differs between low-risk nulliparous and multiparous women at 39-41 weeks of gestation.

METHODS

This is a secondary analysis of an observational obstetrics cohort of maternal-neonatal dyads at 25 hospitals. Low-risk women with nonanomalous singletons who delivered between 39 0/7 and 41 6/7 weeks of gestation were included. The composite neonatal adverse outcome included 5-minute Apgar score less than five, ventilator support or cardiopulmonary resuscitation, seizure, hypoxic ischemic encephalopathy, sepsis, bronchopulmonary dysplasia, persistent pulmonary hypertension, necrotizing enterocolitis, birth injury or perinatal death. The composite maternal adverse outcome included infection, third- or fourth-degree perineal laceration, thromboembolism, transfusion of blood products, or maternal death. Small for gestational age (SGA), large for gestational age (LGA), and shoulder dystocia requiring maneuvers were also evaluated. Multivariable regression was used to estimate adjusted relative risks (aRRs) and adjusted odds ratios (aORs) with 95% CIs.

RESULTS

Of the 115,502 women in the overall cohort, 39,870 (34.5%) met eligibility criteria for this analysis; 18,245 (45.8%) were nulliparous. The risk of the composite neonatal adverse outcome (1.5% vs 1.0%, aRR 1.80, 95% CI 1.48-2.19), composite maternal adverse outcome (15.1% vs 3.3%, aRR 5.04, 95% CI 4.62-5.49), and SGA (8.9% vs 5.8%, aOR 1.45, 95% CI 1.33-1.57) was significantly higher in nulliparous than multiparous patients. The risk of LGA (aOR 0.65, 95% CI 0.60-0.71) and shoulder dystocia with maneuvers (aRR 0.68, 95% CI 0.60-0.77) was significantly lower in nulliparous rather than multiparous patients.

CONCLUSION

The risk of composite adverse outcomes and SGA among low-risk nulliparous women at 39-41 weeks of gestation is significantly higher than among multiparous counterparts. However, nulliparous women had a lower risk of shoulder dystocia with maneuvers and LGA.

First trimester fasting plasma glucose screen in advanced maternal age women: a cost-effectiveness analysis

BACKGROUND

The prevalence of preexisting type 2 diabetes mellitus (T2DM) in the United States is on the rise. Women of advanced maternal age (AMA, ≥35 years) are more likely to have preexisting T2DM in pregnancy because glucose intolerance increases with age. Diabetes in pregnancy is associated with significant maternal and neonatal morbidity and mortality, and earlier treatment initiation improves pregnancy outcomes. However, maternal age is not currently recognized as an independent risk factor that warrants diabetes screening prior to the traditional screen at 24-28 weeks gestation.

OBJECTIVE

To evaluate the cost-effectiveness of screening all AMA women with a first trimester fasting plasma glucose (FPG) test for earlier diagnosis and management of preexisting T2DM.

STUDY DESIGN

A decision-analytic model was created to compare pregnancy outcomes in AMA women who undergo a first trimester FPG test vs third trimester oral glucose tolerance test alone. Probabilities were obtained from the literature. Outcomes examined included preeclampsia, preterm delivery, macrosomia, shoulder dystocia, brachial plexus injury (BPI), intrauterine fetal demise (IUFD), cerebral palsy, and neonatal death. The cost, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio of the first trimester screening strategy were examined as well. Sensitivity analyses and a Monte Carlo simulation were performed to test the model's robustness.

RESULTS

In AMA women, screening for preexisting T2DM in the first trimester with an FPG test resulted in fewer cases of preeclampsia, preterm delivery, BPI, IUFD, cerebral palsy, and neonatal death compared to performing a third trimester oral glucose tolerance test alone, and is cost-effective. Monte Carlo analysis incorporating the distribution of all probabilities showed that first trimester FPG screening remained cost-effective as long as the incremental cost of initiating diabetes treatment in the first trimester was less than $150,000 and the cost of the FPG screen was less than $2700.

CONCLUSION

Compared to third trimester oral glucose tolerance test alone, performing a first trimester FPG screen in AMA women is cost-saving and more effective.

Does induction of labor at term increase the risk of cesarean section in advanced maternal age? A systematic review and meta-analysis

BACKGROUND

Women of advanced maternal age, defined as ≥ 35 years at delivery, are at increased risk of multiple complications during pregnancy, with perinatal death being one of the most feared. For instance, the risk of stillbirth at term in this subgroup of women is higher than in younger women, and particularly high beyond 39 weeks of gestation. Induction of labor at 39-40 weeks might help prevent some cases of perinatal death, however, the fact that induction of labor has been historically associated with an increased risk of cesarean delivery and the knowledge that advanced maternal age is an independent risk factor for cesarean delivery are some of the major reasons why clinicians are reluctant to offer elective induction of labor in this particular group.

OBJECTIVE

The aim of the study was to assess if induction of labor in advanced maternal age was associated with increased rates of cesarean delivery when compared to expectant management.

MATERIAL AND METHODS

We performed an electronic search limited to published articles available between January 2000 and March 2020. Randomized clinical trials and retrospective studies with large cohorts comparing induction of labor with expectant management in singleton pregnancies at term, of women aged ≥ 35 years were included. The primary outcome was the rate of cesarean delivery in induction of labor versus expectant management, and secondary outcomes were the occurrence of assisted vaginal delivery and postpartum hemorrhage.

RESULTS

Eight studies, including 81151 pregnancies (26,631 in the induction group and 54,520 expectantly managed), were included in the analysis. Six of the included studies were randomized clinical trials with the remaining two being observational and retrospective cohort studies. Induction of labor was not associated with a significant increased risk of cesarean delivery (OR 0.97, 95 % CI 0.86-1.1), assisted vaginal delivery (OR 1.12, 95 % CI 0.96-1.32) or postpartum hemorrhage (OR 1.11, 95 % CI 0.88-1.41).

DISCUSSION

The belief that induction of labor is associated with an increased risk of cesarean delivery is based on the results of retrospective studies comparing induction with spontaneous labor at the same gestational age. However, at any point in a pregnancy, the comparison should be between induction of labor and expectant management, with the latter contributing to a pregnancy of greater gestation age and not always leading to spontaneous labor. When comparing induction to expectant management, our study shows no significant increase of cesarean section, assisted vaginal delivery or postpartum hemorrhage. Our study was not powered to assess neonatal outcomes, and additional research is needed to confirm whether induction of labor might have a positive effect in preventing stillbirth.

CONCLUSION

Induction of labor at term in advanced maternal age has no significant impact on cesarean delivery rates, assisted vaginal delivery or postpartum hemorrhage, giving additional reassurance to obstetricians who would consider this intervention in this particular subgroup.

Risk of adverse pregnancy outcomes of late- and postterm pregnancies in advanced maternal age: A national cohort study

Introduction

There is an increase in women delivering ≥35 years of age. We analyzed the association between advanced maternal age and pregnancy outcomes in late‐ and postterm pregnancies.

Material and methods

A national cohort study was performed on obstetrical low‐risk women using data from the Netherlands Perinatal Registry from 1999 to 2010. We included women ≥18 years of age with a singleton pregnancy at term. Women with a pregnancy complicated by congenital anomalies, hypertensive disorders or diabetes mellitus were excluded. Composite adverse perinatal outcome was defined as stillbirth, neonatal death, meconium aspiration syndrome, 5‐minute Apgar score <7, neonatal intensive care unit admittance and sepsis. Composite adverse maternal outcome was defined as maternal death, placental abruption and postpartum hemorrhage of >1000 mL.

Results

We stratified the women into three age groups: 18‐34 (n = 1 321 366 [reference]); 35‐39 (n = 286 717) and ≥40 (n = 40 909). Composite adverse perinatal outcome occurred in 1.6% in women aged 18‐34, 1.7% in women aged 35‐39 (relative risk [RR] 1.06, 95% confidence interval [95% CI] 1.03‐1.08) and 2.2% in women aged ≥40 (RR 1.38, 95% CI 1.29‐1.47), with 5‐minute Apgar score <7 as the factor contributing most to the outcome. Composite adverse maternal outcome occurred in 4.6% in women aged 18‐34, 5.0% in women aged 35‐39 (RR 1.08, 95% CI 1.06‐1.10) and 5.2% in women aged ≥40 (RR 1.14, 95% CI 1.09‐1.19), with postpartum hemorrhage >1000 mL as the factor contributing most to the outcome. In all age categories, the risk of adverse pregnancy outcomes was higher for nulliparous than for multiparous women. The risk of adverse outcomes increased in both nulliparous and parous women with advancing gestational age. When adjusted for parity, onset of labor and gestational age, advanced maternal age is associated with an increase in both composite adverse perinatal and maternal outcomes.

Conclusions

The risk of adverse pregnancy outcome increases with advancing maternal age. Women aged ≥40 have an increased risk of adverse perinatal and maternal outcome when pregnancy goes beyond 41 weeks.

Guideline No. 393-Diabetes in Pregnancy

OBJECTIVES

This guideline reviews the evidence relating to the diagnosis and obstetrical management of diabetes in pregnancy.

OUTCOMES

The outcomes evaluated were short and long-term maternal outcomes including pre-eclampsia, Caesarean section, future diabetes and other cardiovascular complications; and fetal outcomes including congenital anomalies, stillbirth, macrosomia, birth trauma, hypoglycemia and long-term effects.

EVIDENCE

Published literature was retrieved through searches of PubMed and The Cochrane Library using appropriate controlled vocabulary (MeSH terms "diabetes" and "pregnancy"). Where appropriate, results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits but results were limited to English or French language materials.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care.

SUMMARY STATEMENTS

RECOMMENDATIONS.

The majority of early term elective cesarean sections can be postponed

INTRODUCTION

To minimize the risk of neonatal respiratory morbidity it is recommended that elective cesarean sections should not be done before 39-week gestation unless medically indicated. However, elective cesarean sections are still being performed at early term (at 37⁰-38⁶ weeks gestation) without sound medical indications. In this study, we evaluated the indications for elective cesarean sections performed at early term to assess the proportion of procedures that could possibly have been postponed until ≥39 weeks to avoid neonatal respiratory morbidity.

MATERIAL AND METHODS

Maternal and neonatal information was collected from medical records on all elective cesarean sections performed in singleton pregnancies at ≥37⁰ weeks gestation over a 20-year period in a population with secure ultrasound gestational age assignment. Indications were grouped and uterine scar, breech, or transverse presentation and maternal request classified as nonurgent.

RESULTS

There were 3411 elective cesarean sections performed at ≥37-week gestation, of which 790 (23.2%) were at 37⁰-38⁶ weeks. Medical indications were present for 34% (272/790), but 65.6% (518/790) could possibly have been postponed until ≥39⁰ weeks. Of the neonates 5.7% developed respiratory morbidity if delivery was at 37⁰-38⁶ weeks gestation compared to 2.4% at 39⁰-42¹ weeks gestation (p < .001).

CONCLUSION

Of elective cesarean sections before 39-week gestation two-thirds were done without a clear medical indication, thereby exposing the newborn to an increased risk of respiratory morbidity. Scheduling elective cesarean sections at ≥39-week gestation is important to minimize the risk of neonatal respiratory morbidity, unless a clear medical indication dictates earlier delivery.

Which level of risk justifies routine induction of labor for healthy women?

Although induction of labor can be crucial for preventing morbidity and mortality, more and more women (and their offspring) are being exposed to the disadvantages of this intervention while the benefit is at best small or even uncertain. Characteristics such as an advanced maternal age, a non-native ethnicity, a high Body Mass Index, an artificially assisted conception, and even nulliparity are increasingly considered an indication for induction of labor. Because induction of labor has many disadvantages, a debate is urgently needed on which level of risk justifies routine induction of labor for healthy women, only based on characteristics that are associated with statistically significant small absolute risk differences, compared to others without these characteristics. This commentary contributes to this debate by arguing why induction of labour should not routinely be offered to all women where there is a small increase in absolute risk, and no any other medical risks or complications during pregnancy. To underpin our statement, national data from the Netherlands were used reporting stillbirth rates in groups of women based on their characteristics, for each gestational week from 37 weeks of gestation onwards.

Effects of induction of labor prior to post-term in low-risk pregnancies: a systematic review

OBJECTIVE

The objective of this review was to identify, assess and synthesize the best available evidence on the effects of induction prior to post-term on the mother and fetus. Maternal and fetal outcomes after routine labor induction in low-risk pregnancies at 41+0 to 41+6 gestational weeks (prior to post-term) were compared to routine labor induction at 42+0 to 42+6 gestational weeks (post-term).

INTRODUCTION

Induction of labor when a pregnancy exceeds 14 days past the estimated due date has long been used as an intervention to prevent adverse fetal and maternal outcomes. Over the last decade, clinical procedures have changed in many countries towards earlier induction. A shift towards earlier inductions may lead to 15-20% more inductions. Given the fact that induction as an intervention can cause harm to both mother and child, it is essential to ensure that the benefits of the change in clinical practice outweigh the harms.

INCLUSION CRITERIA

This review included studies with participants with expected low-risk deliveries, where both fetus and mother were considered healthy at inclusion and with no known risks besides the potential risk of the ongoing pregnancy. Included studies evaluated induction at 41+1-6 gestational weeks compared to 42+1-6 gestational weeks. Randomized control trials (n = 2), quasi-experimental trials (n = 2), and cohort studies (n = 3) were included. The primary outcomes of interest were cesarean section, instrumental vaginal delivery, low Apgar score (≤ 7/5 min.), and low pH (< 7.10). Secondary outcomes included additional indicators of fetal or maternal wellbeing related to prolonged pregnancy or induction.

METHODS

The following information sources were searched for published and unpublished studies: PubMed, CINAHL, Embase, Scopus, Swemed+, POPLINE; Cochrane, TRIP; Current Controlled Trials; Web of Science, and, for gray literature: MedNar; Google Scholar, ProQuest Nursing & Allied Health Source, and guidelines from the Royal College of Obstetricians and Gynaecologists, and American College of Obstetricians and Gynecologists, according to the published protocol. In addition, OpenGrey and guidelines from the National Institute for Health and Care Excellence, World Health Organization, and Society of Obstetricians and Gynaecologists of Canada were sought. Included papers were assessed by all three reviewers independently using the Joanna Briggs Institute System for the Unified Management, Assessment and Review of Information (JBI SUMARI). The standardized data extraction tool from JBI SUMARI was used. Data were pooled in a statistical meta-analysis model using RevMan 5, when the criteria for meta-analysis were met. Non-pooled results were presented separately.

RESULTS

Induction at 41+0-6 gestational weeks compared to 42+0-6 gestational weeks was found to be associated with an increased risk of overall cesarean section (relative risk [RR] = 1.11, 95% confidence interval [CI] 1.09-1.14), cesarean section due to failure to progress (RR = 1.43, 95% CI 1.01-2.01), chorioamnionitis (RR = 1.13, 95% CI 1.05-1.21), labor dystocia (RR = 1.29, 95% CI 1.22-1.37), precipitate labor (RR = 2.75, 95% CI 1.45-5.2), uterine rupture (RR = 1.97, 95% CI 1.54-2.52), pH < 7.10 (RR = 1.9, 95% CI 1.48-2.43), and a decreased risk of oligohydramnios (RR = 0.4, 95% CI 0.24-0.67) and meconium stained amniotic fluid (RR = 0.82, 95% CI 0.75-0.91). Data lacked statistical power to draw conclusions on perinatal death. No differences were seen for postpartum hemorrhage, shoulder dystocia, meconium aspiration, 5-minute Apgar score < 7, or admission to neonatal intensive care unit. A policy of awaiting spontaneous onset of labor until 42+0-6 gestational weeks showed, that approximately 70% went into spontaneous labor.

CONCLUSIONS

Induction prior to post-term was associated with few beneficial outcomes and several adverse outcomes. This draws attention to possible iatrogenic effects affecting large numbers of low-risk women in contemporary maternity care. According to the World Health Organization, expected benefits from a medical intervention must outweigh potential harms. Hence, our results do not support the widespread use of routine induction prior to post-term (41+0-6 gestational weeks).

[To the question of elective induction of labor at 39 weeks of gestation, the answer lies in the question]

The goal of induction of labor is to achieve vaginal delivery when the benefits of expeditious delivery outweigh the risks of continuing the pregnancy. In order to correctly understand the problematic of the elective induction of labor at 39 weeks of gestation (WG), two questions must be raised. (i) What is the perinatal mortality evolution according the gestational age at delivery? All the most recent and methodologically well-conducted studies are convergent: they show that the fetal mortality risk exceeds the perinatal/infant (during the first year of life) mortality risk from 39 WG. The benefit/risk balance related to the expectant management is therefore reversed from 39 WG in favor of the elective induction of labor when the considered issue is the perinatal mortality. (ii) What are the associated risks with elective induction of labor? While some observational studies suggested that the elective induction of labor after 37 WG was associated with an increased risk of cesarean sections, these studies presented a major methodological bias: an error in the control group selection. Indeed, the control group consisted of women in spontaneous labor, whereas the appropriate comparison group must be an expectant management group. Several large cohort studies using a rigorous methodology have shown that elective induction of labor at 39 WG reduces the cesarean section risk compared to an expectant management. Three systematic reviews with meta-analysis of randomized controlled trials comparing induction of labor with expectant management were published: two showed that the cesarean section risk was lowered with the induction of labor compared to an expectant management and the third that the cesarean section rates were similar. Finally, the most recent randomized controlled trial, published in 2016, showed no significant difference between the 2 arms in the cesarean section rate. In all, the most recent literature data, free from comparative bias, show that elective induction of labor at term is associated with a significant reduction in the cesarean section risk and perinatal morbidity and mortality compared to an expectant management.

Late-preterm infants, early-term infants, and timing of elective deliveries; current status in a Korean medical center

OBJECTIVE

The aim of this study was to examine the current perinatal outcomes among infants born late-preterm and early-term compared to those born full-term and evaluate the optimal gestational age for delivery.

METHODS

We performed a retrospective cohort study for births occurred at Seoul St. Mary's Hospital over the past 7 years. Statistical comparison was performed using χ² test and multivariable logistic regression models.

RESULTS

A total of 7580 women met the study criteria. Compared to 39 weeks, delivery at late-preterm and early-term had higher risk of composite morbidity, including respiratory morbidities, intracranial hemorrhage (ICH), and admission to neonatal intensive care unit (NICU) (34 weeks adjusted odds ratio [aOR]: 132.54; 95% confidence interval (CI): 74.00-240.10; 37 weeks aOR: 2.14; 95%CI: 1.65-2.77). The risks of sepsis and necrotizing enterocolitis in deliveries before 36 weeks and the risk of feeding difficulty in deliveries before 37 weeks were significantly higher than those of 39 weeks. Neonatal morbidity at deliveries was not significantly different between 38 and 39 weeks.

CONCLUSIONS

Neonatal morbidities at late-preterm births are significant and surveillance for them seems increasing. Obstetricians should recognize the risk of respiratory morbidity, ICH, and NICU admission for deliveries before 38 weeks' gestation.

Optimal timing of delivery for women with breast cancer, according to cancer stage and hormone status: a decision-analytic model

OBJECTIVE

To compare strategies for the timing of delivery in women with breast cancer and known cancer stage or hormone receptor subtype, and to determine the optimal gestational age for induction in regards to maternal-fetal outcomes.

STUDY DESIGN

A decision-analytic model was designed comparing eight different strategies for scheduled delivery at 30, 31, 32, 33, 34, 35, 36, and 37 weeks gestation. Optimal breast cancer treatment was assumed to be delayed until after delivery. Baseline estimates of the stage- and subtype-specific mortality and the impact of delayed cancer treatment on 5-year survival rates were obtained from the literature. Outcomes factored into the model included the risk of intrauterine fetal demise, spontaneous delivery, respiratory distress syndrome, cerebral palsy, and neonatal demise at each gestational age. Univariate sensitivity analyses and Monte Carlo simulations were performed to test the robustness of our model.

RESULTS

For women with stage I-II breast cancer, delivery at 36 weeks yielded the highest number of overall quality-adjusted life years (QALYs), while maternal QALYs were maximized with delivery at 34 weeks. For stage III and IV disease, maternal QALYs were maximized at 31 and 30 weeks, respectively. For women with estrogen or progesterone receptor-positive, human epidermal receptor-2 negative breast cancer, both maternal QALYs and overall QALYs were maximized with delivery at 36 weeks. More aggressive biological phenotypes were similarly associated with optimal delivery at decreasing gestational age. Our model was heavily driven by the baseline probability of maternal death within 5 years, in addition to the expected progression of disease and decreases in survival rates with each week of non-treatment, and remained robust across reasonable ranges for all variables of interest.

CONCLUSIONS

For women with breast cancer diagnosed during pregnancy, decisions regarding timing of delivery should take into consideration both cancer stage and hormone receptor subtype.

The effect of maternal age on fetal and neonatal mortality

OBJECTIVE

Determine the gestational age at which the risk of fetal or neonatal death associated with delaying delivery by 1 week exceeds the risk of neonatal death associated with immediate delivery, stratified by maternal age intervals.

STUDY DESIGN

We conducted a retrospective cohort study of live births, stillbirths and neonatal deaths that occurred in the United States between 2010 and 2013 using birth data. Women were classified into six age categories. Singleton, non-anomalous pregnancies without hypertensive disease or diabetes were included. Relative risks were obtained using a generalized linear model comparing the rate of death associated with immediate delivery to those of expectant management.

RESULTS

For all age groups with the exception of women 44 years and older, immediate delivery was associated with lower relative risk of death by 39 weeks. For <25, 25 to 29, 30 to 34, 35 to 39, 40 to 44, odds ratios (OR) and confidence intervals (CI) were 1.0 (0.32 to 3.10), 0.67 (0.19 to 2.37), 0.80 (0.21 to 2.98), 0.67 (0.19 to 2.36) and 0.45 (0.16 to 1.31), respectively. In women 44 years and older, immediate delivery was associated with a lower relative risk of death by 38 weeks (OR: 0.35, CI: 0.14 to 0.90).

CONCLUSION

Women greater than 44 years old may benefit from delivery by 38 weeks gestational age to reduce the risk of stillbirth.

Gastroschisis: mortality risks with each additional week of expectant management

BACKGROUND

Prior studies have evaluated the overall risk of stillbirth in pregnancies with fetal gastroschisis. However, the gestational age at which mortality is minimized, balancing the risk of stillbirth against neonatal mortality, remains unclear.

OBJECTIVE

We sought to evaluate the gestational age at which prenatal and postnatal mortality risk is minimized for fetuses with gastroschisis.

STUDY DESIGN

This was a retrospective cohort study of singleton pregnancies delivered between 24 0/7 and 39 6/7 weeks, using 2005 through 2006 US national linked birth and death certificate data. Among pregnancies with fetal gastroschisis, prospective risk of stillbirth and risk of infant death were determined for each gestational age week. Risk of infant death with delivery was further compared to composite fetal/infant mortality risk with expectant management for 1 additional week.

RESULTS

Among 2,119,049 pregnancies, 860 cases (0.04%) of gastroschisis were identified. The overall stillbirth rate among gastroschisis cases was 4.8%, and infant death occurred in 8.3%. Prospective risk of stillbirth became more consistently elevated beginning at 35 weeks, rising to 13.9 per 1000 pregnancies (95% confidence interval, 10.8-17.1) at 39 weeks. Risk of infant death concurrently nadired in the third trimester, ranging between 62.4-66.8 per 1000 live births between 32-39 weeks. Comparing mortality with expectant management vs delivery, relative risk was significantly greater with expectant management between 37-39 weeks, reaching 1.90 (95% confidence interval, 1.73-2.08) at 39 weeks with a number needed to deliver of 17.49 (95% confidence interval, 15.34-20.32) to avoid 1 excess death.

CONCLUSION

Risk of prenatal and postnatal mortality for fetuses with gastroschisis may be minimized with delivery as early as 37 weeks.

Diabetes in Pregnancy

OBJECTIVE

This guideline reviews the evidence relating to the diagnosis and obstetrical management of diabetes in pregnancy.

OUTCOMES

The outcomes evaluated were short- and long-term maternal outcomes, including preeclampsia, Caesarean section, future diabetes, and other cardiovascular complications, and fetal outcomes, including congenital anomalies, stillbirth, macrosomia, birth trauma, hypoglycemia, and long-term effects.

EVIDENCE

Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate controlled vocabulary (MeSH terms "diabetes" and "pregnancy"). Where appropriate, results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1).

SUMMARY STATEMENTS

Recommendations It is recognized that the use of different diagnostic thresholds for the "preferred" and "alternative" strategies could cause confusion in certain settings. Despite this, the committee has identified the importance of remaining aligned with the current Canadian Diabetes Association 2013 guidelines as being a priority. It is thus recommended that each care centre strategically align with 1 of the 2 strategies and implement protocols to ensure consistent and uniform reporting of test results.

The risk of fetal death in nonanomalous pregnancies affected by polyhydramnios

OBJECTIVE

The objective of the study was to evaluate the ongoing risk of intrauterine fetal demise (IUFD) in nonanomalous pregnancies affected by polyhydramnios.

STUDY DESIGN

We analyzed a retrospective cohort of all singleton, nonanomalous births in California between 2005 and 2008 as recorded in a statewide birth certificate registry. We included all births between 24+0 and 41+6 weeks' gestational age, excluding multiple gestations, major congenital anomalies, and pregnancies affected by oligohydramnios. Polyhydramnios was identified by International Classification of Diseases, ninth revision, codes. χ(2) tests were used to compare the dichotomous outcomes, and multivariable logistic regression analyses were then performed to control for potential confounders. We analyzed the data for pregnancies affected and unaffected by polyhydramnios. The IUFD risk was expressed as a rate per 10,000.

RESULTS

The risk of IUFD in pregnancies affected by polyhydramnios was greater at every gestational age compared with unaffected pregnancies. The IUFD risk in pregnancies affected by polyhydramnios was more than 7 times higher than unaffected pregnancies at 37 weeks at a rate of 18.0 (95% confidence interval [CI], 9.0-32.6) vs 2.4 (95% CI, 2.0-2.5) and was 11-fold higher by 40 weeks' gestational age at a rate of 66.3 (95% CI, 10.8-68.6) vs 6.0 (95% CI, 5.1-6.3) in unaffected pregnancies. When adjusted for multiple confounding variables, the presence of polyhydramnios remained associated with an increased odds of IUFD in nonanomalous singleton pregnancies, with an adjusted odds ratio of 5.5 (95% CI, 4.1-7.6).

CONCLUSION

Ongoing risk of IUFD is greater in low-risk pregnancies affected by polyhydramnios at all gestational ages compared with unaffected pregnancies with the greatest increase in risk at term. Although further study is needed to explore the underlying etiology of polyhydramnios in these cases, the identification of polyhydramnios alone may warrant increased antenatal surveillance.

Gestational age-specific neonatal morbidity among pregnancies complicated by advanced maternal age: a population-based retrospective cohort study

OBJECTIVE

Compare significant neonatal morbidity frequency differences in advanced maternal age (AMA) versus non-AMA pregnancies, assessing which gestational week is associated with the lowest morbidity risk.

METHODS

Population-based retrospective cohort study. Adverse neonatal outcome frequency differences were stratified by each week of gestation. Multivariate logistic regression estimated the relative risk (RR) of composite neonatal morbidity for women aged 35-39, 40-44, 45-49 and 50-55 versus 18-34 years, adjusted sequentially for relevant risk factors.

RESULTS

Neonatal morbidity decreased with each advancing week of term gestation, lowest at 39 weeks for all the groups. Adverse neonatal outcome risk for births to AMA women increased at 40 weeks: 35-39 years adjRR 1.12 [1.01-1.24] and ≥40 years 1.24 [1.01-1.52]. Each older maternal age category had increased risk for overall neonatal morbidity: 35-39 years adjRR 1.11 [95% CI 1.08-1.15], 40-44 years 1.21 [95% CI 1.14-1.29] and 45-49 years 1.34 [95% CI 1.05-1.69].

CONCLUSIONS

Lowest neonatal morbidity risk is at 39-week gestation with a significantly increased risk observed thereafter, especially in women ≥40 years.

The mortality risk of expectant management compared with delivery stratified by gestational age and race and ethnicity

OBJECTIVE

The objective of the study was to compare the mortality risk of expectant management with the risk of delivery at each week of term pregnancy in 4 racial/ethnic groups.

STUDY DESIGN

This was a retrospective cohort study of all nonanomalous, term deliveries in California from 1997 to 2006 among white, black, Hispanic, and Asian women. In each racial/ethnic group, we compared the risk of infant death at each week with a composite risk representing the mortality risk of 1 week of expectant management.

RESULTS

The risk of stillbirth and infant death is highest in black women (stillbirth risk: 18.0 per 10,000, infant death: 24.4 per 10,000, compared with 9.4 per 10,000 and 10.8 per 10,000 in white women, respectively; P < .001). Although absolute risks differ by race/ethnicity, the composite risk of expectant management does not surpass the risk of delivery until 39 weeks in any group. At 39 weeks these absolute risk differences are low, however, with a number needed to deliver to prevent 1 death ranging from 751 (among black women) to 2587 (among Asian women).

CONCLUSION

The mortality risk of expectant management exceeds the risk of delivery at 39 weeks in all racial/ethnic groups, despite variation in absolute risks.

Reduction in stillbirths at term after new birth induction paradigm: results of a national intervention

OBJECTIVE

The risk of fetal death increases steeply after 42 gestational weeks. Since 2009, Denmark has had a more proactive policy including prevention of prolonged pregnancy, and early intervention in women with diabetes, preeclampsia, high body mass index and of a higher age group. The aim of this study was to describe the development in fetal deaths with this more proactive birth induction practice, and to identify and quantify contributing factors for this development.

DESIGN

National cohort study.

SETTING

Denmark.

PARTICIPANTS

Delivering women in Denmark, 1 January 2000 to 31 December 2012.

OUTCOME MEASURES

Stillbirths per 1000 women at risk (prospective risk of stillbirth) and per 1000 newborn from 37 and 40 gestational weeks, respectively, through the study period.

RESULTS

During the study period, 829,165 children were live born and 3770 (0.45%) stillborn. Induction of labour increased from 12.4% in year 2000 to 25.1% in 2012 (p<0.001), and the percentage of children born at or after 42 weeks decreased from 8.0% to 1.5% (p<0.001). Through the same period, the prospective risk of stillbirth after 37 weeks fell from 0.70 to 0.41/1000 ongoing pregnancies (p<0.001), and from 2.4 to 1.4/1000 newborn (p<0.001). The regression analysis confirmed the inverse association between year of birth and risk of stillbirth. The lowest risk was observed in the years 2011-2012 as compared with years 2000-2002 with a fully adjusted HR of 0.69 (95% CI 0.57 to 0.83). The general earlier induction, the focused earlier induction of women with body mass index >30, twins, and of women above 40 years and a halving of smoking pregnant women were all independent contributing factors for the decrease.

CONCLUSIONS

A gradually more proactive and differential earlier labour induction practice is likely to have mainly been responsible for the substantial reduction in stillbirths in Denmark.