The effect of gestational age on neonatal outcome in low-risk singleton term deliveries

Adverse neonatal outcomes and associated factors among mothers who gave birth through induced and spontaneous labor in public hospitals of Awi zone, Northwest Ethiopia: a comparative cross-sectional study

BACKGROUND

Adverse neonatal outcomes are one of the most common causes of neonatal mortality and morbidity. Empirical evidence across the world shows that induction of labor potentiates adverse neonatal outcomes. In Ethiopia, there has been limited data that compares the frequency of adverse neonatal outcomes between induced and spontaneous labor.

OBJECTIVES

To compare the prevalence of adverse neonatal outcomes between induced and spontaneous labor and to determine associated factors among women who gave birth in public hospitals of Awi Zone, Northwest Ethiopia.

METHODS

A comparative cross-sectional study was conducted at Awi Zone public hospitals from May 1 to June 30, 2022. A simple random sampling technique was employed to select 788 (260 induced and 528 spontaneous) women. The collected data were analyzed using statistical package for social science (SPSS) software version 26. The Chi-square test and an independent t-test were used for categorical and continuous variables, respectively. A binary logistic regression was used to assess the association between the outcome and explanatory variables. In the bivariate analysis, a p-value ≤ 0.2 at a 95% confidence interval was used to consider the variables in the multivariate analysis. Finally, statistical significance was stated at a p-value of less than 0.05.

RESULT

The adverse neonatal outcomes among women who gave birth through induced labor were 41.1%, whereas spontaneous labor was 10.3%. The odds of adverse neonatal outcomes in induced labor were nearly two times higher than in spontaneous labor (AOR = 1.89, 95% CI: 1.11-3.22). No education (AOR = 2.00, 95% CI: 1.56, 6.44), chronic disease (AOR = 3.99, 95% CI: 1.87, 8.52), male involvement (AOR = 2.23, 95% CI: 1.23, 4.06), preterm birth (AOR = 9.83, 95% CI: 8.74, 76.37), operative delivery (AOR = 8.60, 95% CI: 4.63, 15.90), cesarean section (AOR = 4.17, 95% CI: 1.94, 8.95), and labor complications (AOR = 5.16, 95% CI: 2.90, 9.18) were significantly associated factors with adverse neonatal outcomes.

CONCLUSION AND RECOMMENDATION

Adverse neonatal outcomes in the study area were higher. Composite adverse neonatal outcomes were significantly higher in induced labor compared to spontaneous labor. Therefore, it is important to anticipate the possible adverse neonatal outcomes and plan management strategies while conducting every labor induction.

Evidence around early induction of labor in women of advanced maternal age and those using assisted reproductive technology

Worldwide, there has been a trend toward later motherhood. Concurrently, the incidence of subfertility has been on the rise, necessitating conception using assisted reproductive technologies (ARTs). These pregnancies are considered high risk due to fetal complications such as antepartum stillbirth and growth restriction and maternal complications such as increase in maternal morbidity and mortality. Early induction of labor can help to mitigate these risks. However, this has to be balanced against the iatrogenic harms of earlier delivery to both the baby, including respiratory distress and NICU stay, and the mother who might experience longer labor and other complications such as uterine hyperstimulation. Induction of labor at 39 weeks is the optimal timing for preventing antepartum stillbirth and avoiding iatrogenic harm. Delivery by elective cesarean section is not advocated as its benefits in these patients are unclear compared with the short- and long-term complications of a major abdominal surgery.

Rates of Neuropsychiatric Disorders and Gestational Age at Birth in a Danish Population

IMPORTANCE

Nonoptimal gestational durations could be associated with neurodevelopmental disabilities, yet evidence regarding finer classification of gestational age and rates of multiple major neuropsychiatric disorders beyond childhood is limited.

OBJECTIVE

To comprehensively evaluate associations between 6 gestational age groups and rates of 9 major types and 8 subtypes of childhood and adult-onset neuropsychiatric disorders.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study evaluated data from a nationwide register of singleton births in Denmark from January 1, 1978, to December 31, 2016. Data analyses were conducted from October 1, 2019, through November 15, 2020.

EXPOSURES

Gestational age subgroups were classified according to data from the Danish Medical Birth Register: very preterm (20-31 completed weeks), moderately preterm (32-33 completed weeks), late preterm (34-36 completed weeks), early term (37-38 completed weeks), term (39-40 completed weeks, reference), and late or postterm (41-45 completed weeks).

MAIN OUTCOMES AND MEASURES

Neuropsychiatric diagnostic records (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes F00-F99) were ascertained from the Danish Psychiatric Central Register up to August 10, 2017. Poisson regression was used to estimate the incidence rate ratio (IRR) and 95% CI for neuropsychiatric disorders, adjusting for selected sociodemographic factors.

RESULTS

Of all 2 327 639 singleton births studied (1 194 925 male newborns [51.3%]), 22 647 (1.0%) were born very preterm, 19 801 (0.9%) were born moderately preterm, 99 488 (4.3%) were born late preterm, 388 416 (16.7%) were born early term, 1 198 605 (51.5%) were born at term, and 598 682 (25.7%) were born late or postterm. A gradient of decreasing IRRs was found from very preterm to late preterm for having any or each of the 9 neuropsychiatric disorders (eg, very preterm: IRR, 1.49 [95% CI, 1.43-1.55]; moderately preterm: IRR, 1.23 [95% CI, 1.18-1.28]; late preterm: IRR, 1.17 [95% CI, 1.14-1.19] for any disorders) compared with term births. Individuals born early term had 7% higher rates (IRR, 1.07 [95% CI, 1.06-1.08]) for any neuropsychiatric diagnosis and a 31% higher rate for intellectual disability (IRR, 1.31 [95% CI, 1.25-1.37]) compared with those born at term. The late or postterm group had lower IRRs for most disorders, except pervasive developmental disorders, for which the rate was higher for postterm births compared with term births (IRR, 1.06 [95% CI, 1.03-1.09]).

CONCLUSIONS AND RELEVANCE

Higher incidences of all major neuropsychiatric disorders were observed across the spectrum of preterm births. Early term and late or postterm births might not share a homogeneous low risk with individuals born at term. These findings suggest that interventions that address perinatal factors associated with nonoptimal gestation might reduce long-term neuropsychiatric risks in the population.

Early term birth is associated with the risk of preterm and recurrent early term birth in women with 3 consecutive deliveries

BACKGROUND

We assessed the association of early term at first birth (ETB) with the risk of preterm birth (PTB) and ETB in women with 3 consecutive deliveries.

METHODS

We conducted a retrospective cohort study of all women with 3 consecutive singleton births at a single institute from 1994 to 2013. The risk of PTB (<37 weeks), spontaneous PTB and ETB (37-38 weeks) in the 3^rd delivery was explored.

RESULTS

Of 49,259 women delivered in our center during the study period, 4038 met inclusion criteria. The rate for subsequent PTB, spontaneous PTB and recurrent ETB in the 3^rd delivery significantly increased as the number of prior ETBs increased. The order of a single prior ETB in one of the first two deliveries was differently associated with the risk of complications in the 3^rd delivery, which was higher when the prior ETB was more recent to the third delivery.

CONCLUSION

A history of ETB is associated with the risk of future PTB and recurrent ETB. The risk is related to the number and order of prior ETBs.

Neonatal Adverse Outcomes of Induction and Expectant Management in Fetal Growth Restriction: A Systematic Review and Meta-Analysis

Background and Objective: Fetal growth restriction (FGR) is a pathological condition in which the fetus cannot reach its expected growth potential. When it is diagnosed as a suspected FGR, it remains an unsolved problem whether to direct induction or continue expectant management. To effectively reduce the incidence of neonatal adverse outcomes, we aimed to evaluate whether either method was associated with a lower incidence of neonatal adverse outcomes. Methods: We searched the relevant literature through the PubMed, Web of Science, and Cochrane Library from inception to January 10, 2020. We defined induction as the experimental group and expectant management as the control group. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models owing to heterogeneity. Furthermore, we conducted a sensitivity analysis to explore the robustness of the included literature. We used the Newcastle-Ottawa scale (NOS) to evaluate the quality of the available studies. We applied the funnel plot to describe the publication bias. Additionally, subgroup analysis based on the study method, sample size, area, NOS score, Apgar score <7 at 5 min, definition of suspected FGR, severity, and neonatal adverse outcomes were performed to further evaluate the differences between the induction and expectant management. Results: Our study included a total of eight articles with 6,706 patients, which consisted of four randomized controlled trials (RCTs), three retrospective cohort studies, and one prospective cohort study. The total pooled OR and 95% CI between the induction group and the expected management group was 1.38 (95% CI, 0.84-2.28) in the random model. The heterogeneity was I 2 = 84%, P < 0.01. The sensitivity analysis showed that the neonatal adverse outcomes of induction vs. expectant management still presented similar outcomes after omitting of any one of these studies. The funnel plot and linear regression equation showed that there was no publication bias in our study (P = 0.75). Subgroup analysis showed that induction increased the neonatal adverse outcome risks of hypoglycemia and respiratory insufficiency (ORneonatal hypoglycaemia = 8.76, 95% CI: 2.57-29.90; ORrespiratory insufficiency = 1.74, 95% CI: 1.35-2.24, respectively). However, no significant differences were observed based on the other subgroups (all P > 0.05). Conclusion: Regardless of induction or expectant management of a suspected FGR, the neonatal adverse outcomes showed no obvious differences. More studies should be conducted and confounding factors should be taken into consideration to elucidate the differential outcomes of the two approaches for suspected FGR.

Timing and mode of delivery with advancing maternal age

In 2017, 23% of all live births in the United Kingdom were to women aged over 35 years. Decisions around the timing of delivery for such women must balance the risks of prolongation of the pregnancy and of iatrogenic harm from timed delivery. Women of advanced maternal age have a small age-related elevated risk of term stillbirth. Antenatal monitoring and the route of delivery should not differ from those for younger women. The induction of labour at 39 weeks for such women does not appear to increase the risk of emergency caesarean section or to have any short-term adverse effects on mother or baby. There have been no studies on the long-term effects of induction in this group. Nevertheless, it seems reasonable to offer women of advanced maternal age, induction of labour at 39 weeks where resources are available to safely provide this.

Adverse perinatal outcomes in 665,244 term and post-term deliveries-a Norwegian population-based study

OBJECTIVE

To assess the prevalence and risk of adverse perinatal outcomes in early-term (37⁺⁰-38⁺⁶ weeks), full-term (39⁺⁰-40⁺⁶ weeks), late-term (41⁺⁰-41⁺⁶ weeks), and post-term (>42⁺⁰ weeks) deliveries with spontaneous labor onset.

STUDY DESIGN

A population-based cohort with data from the Medical Birth Registry Norway (MBRN) and Statistics Norway (SSB) was conducted. The study population consisted of 665,244 women with cephalic singleton live births at term or post-term with spontaneous labor onset during the period of 1999-2014 in Norway. Maternal, obstetric, and fetal characteristics were obtained from the MBRN. Maternal education data were obtained from the SSB. The prevalence rates of adverse perinatal outcomes for each gestational age (GA) group were estimated. Inter-group differences were detected with Chi square tests. Multivariable regression analysis adjusted for maternal age, educational level, smoking, parity, maternal diabetes, and preeclampsia was used to assess adverse outcome prevalence for early- late-, and post-term births compared to full-term births.

RESULTS

Deliveries at early-term were associated with an increased prevalence of neonatal jaundice, polyhydramnios, small for gestational age (SGA) status, respiratory support, and neonatal intensive care unit (NICU) admission compared with deliveries at GAs of 39-43 weeks (p < 0.001). Low 5-min Apgar scores and newborn antibiotic treatment occurred at an increased prevalence in both early-term and post-term infants, relative to the full-term group (p < 0.001). The prevalence of oligohydramnios, meconium-stained amniotic fluid, and newborn birth injuries increased with increasing GA.

CONCLUSIONS

More perinatal morbidity was observed among early-term infants compared to infants with later term deliveries, underscoring the need for cautious management of low-risk early-term deliveries.

The risk of intrapartum/neonatal mortality and morbidity following birth at 37 weeks of gestation: a nationwide cohort study

Objective

To assess intrapartum/neonatal mortality and morbidity risk in infants born at 37 weeks of gestation compared with infants born at 39–41 weeks of gestation.

Design

Nationwide cohort study.

Setting

The Netherlands.

Population

A total of 755 198 women delivering at term of a singleton without congenital malformations during 2010–14.

Methods

We used data from the national perinatal registry (PERINED). Analysis was performed with logistic regression and stratification for the way labour started and type of care.

Main outcome measures

Intrapartum or neonatal mortality up to 28 days and adverse neonatal outcome (neonatal mortality, 5‐minute Apgar <7, and/or neonatal intensive care unit admission).

Results

At 37 weeks of gestation intrapartum/neonatal mortality was 1.10‰ compared with 0.59‰ at 39–41 weeks (P < 0.0001). Adjusted odds ratio (aOR) for 37 weeks compared with 39–41 weeks was 1.84 (95% CI) 1.39–2.44). Adverse neonatal outcome at 37 weeks was 21.4‰ compared with 12.04‰ at 39–41 weeks (P < 0.0001) with an aOR 1.63 (95% CI 1.53–1.74). Spontaneous start of labour at 37 weeks of gestation was significantly associated with increased intrapartum/neonatal mortality with an aOR of 2.20 (95% CI 1.56–3.10), in both primary (midwifery‐led) care and specialist care. Neither induction of labour nor planned caesarean section showed increased intrapartum/neonatal mortality risk.

Conclusions

Birth at 37 weeks of gestation is independently associated with a higher frequency of clinically relevant adverse perinatal outcomes than birth at 39–41 weeks. In particular, spontaneous start of labour at 37 weeks of gestation doubles the risk for intrapartum/neonatal mortality. Extra fetal monitoring is warranted.

Tweetable abstract

Birth at 37 weeks of gestation gives markedly higher intrapartum/neonatal mortality risk than at 39–41 weeks, especially with spontaneous start of labour.

Tweetable abstract

Birth at 37 weeks of gestation gives markedly higher intrapartum/neonatal mortality risk than at 39–41 weeks, especially with spontaneous start of labour.

Delivery at Term: When, How, and Why

There is growing evidence from randomized trials that induction of labor at or near term does not increase cesarean delivery; observational data show that the optimal gestation for spontaneous delivery for the baby is 39 weeks. Elective cesarean at these gestations is also sometimes considered, but evaluating the associated risks is complex. For the baby, although cesarean obviates the risks of labor, it carries a risk of respiratory problems, which may be severe. For the mother, cesarean is more dangerous than vaginal and emergency cesarean is more dangerous than elective. The authors consider the evidence base for near-term induction of labor and cesarean for a range of scenarios.

Effect of early-term birth on respiratory symptoms and lung function in childhood and adolescence

BACKGROUND

Early-term-born subjects, (37-38 weeks' gestation), form a large part of the population and have an increased risk of neonatal respiratory morbidity and childhood respiratory symptoms; there is a paucity of data on their later lung function. We sought to (1) compare lung function at 8-9 and 14-17 years in early-term-born children with full-term-born children (39-43 weeks' gestation); (2) assess the role of caesarean section delivery; and (3) compare respiratory symptoms and diagnosis of asthma.

METHODS

Caucasian, singleton, term births from the Avon Longitudinal Study of Parents and Children (n = 14,062) who had lung spirometry at 8-9 (n = 5,465) and/or 14-17 (n = 3,666) years were classified as early or full term.

RESULTS

At 8-9 years, standardized spirometry measures, although within the normal range, were lower in the early-term-born group, (n = 911), compared to full-term controls (n = 4,554). Delivery by caesarean section did not influence later spirometry, and the effect of early-term birth was not modified by delivery by caesarean section. At 14-17 years, the spirometry measures in the early-term group, (n = 602), were similar to the full-term group (3,064), and the rates of asthma and respiratory symptoms were also similar between the two gestation groups.

CONCLUSIONS

Early-term-born children had lower lung function values at 8-9 years compared to the full-term group, but were similar by 14-17 years of age. Delivery at early term should be avoided due to early and late morbidity. Pediatr Pulmonol. 2016;51:1212-1221. © 2016 Wiley Periodicals, Inc.

The respiratory consequences of early-term birth and delivery by caesarean sections

In England and Wales, 19% of live births in 2012 were at 37-38 weeks' gestation, equating to nearly 140 000 early-term births each year. Since caesarean sections (CS) are often performed at early-term gestations, this accounts for some of the increased proportion of the early-term births. Infants born early-term are at an increased risk of neonatal respiratory morbidity particularly if they are delivered by caesarean section. The long term lung function data are limited but available data suggest that early-term delivery is associated with respiratory morbidity in childhood. CS also appears to be associated with increased neonatal morbidity and future development of respiratory symptoms. However, future studies need to confirm the independent effects of caesarean sections and early-term deliveries particularly for long term outcomes as both are likely to affect the respiratory system differently.