Maternal and Perinatal Outcome After Induction of Labor Versus Expectant Management in Low-risk Pregnancies Beyond Term

Abstract

Background/aim: Due to still controversial discussion regarding appropriate termination of low-risk singleton pregnancies beyond term, this retrospective study aimed to evaluate maternal and perinatal outcomes depending on gestational age and obstetric management.

Patients and methods: This is a retrospective cohort analysis including 3.242 low-risk singleton deliveries at the Department of Obstetrics of the University Hospital of Cologne between 2017 and 2022. According to current national guidelines, the cohort was subdivided into three gestational groups, group 1: 40+0-40+6 weeks, group 2: 40+7-40+10 weeks and group 3>40+10 weeks.

Results: In our cohort, advanced gestational age was associated with higher rates of secondary caesarean sections, lower rates of spontaneous vaginal deliveries, higher rates of meconium-stained amniotic fluid and depressed neonates with APGAR < 7 after 5 min. Analyzing obstetric management, induction of labor significantly increased the rate of secondary sections and reduced the rate of spontaneous deliveries, while the percentage of assistant vaginal deliveries was independent from obstetric management and gestational age. Induction of labor also significantly enhanced the need for tocolytic subpartu and epidural anesthesia and caused higher rates of abnormalities in cardiotocography (CTG), which also resulted in more frequent fetal scalp blood testing; however, the rate of fetal acidosis was independent of both obstetric management and gestational age.

Conclusion: Our study supports expectant management of low-risk pregnancies beyond term, as induction of labor increased the rate of secondary sections and did not improve perinatal outcome.

Keywords: Low-risk pregnancy; delivery mode; induction of labor; maternal outcome; obstetric management beyond term; perinatal outcome.