Outpatient labor induction-Exploring future potential by assessing eligibility in a historical cohort

Abstract

Introduction: Labor induction rates have increased over the last decades, and in many high-income countries, more than one in four labors are induced. Outpatient management of labor induction has been suggested in low-risk pregnancies to improve women's birth experiences while also promoting a more efficient use of healthcare resources. The primary aim of this paper was to assess the proportion of women in a historical cohort that would have been eligible for outpatient labor induction with oral misoprostol. Second, we wanted to report safety outcomes and assess efficacy outcomes for mothers and infants in pregnancies that met the criteria for outpatient care.

Material and methods: Criteria for outpatient labor induction with oral misoprostol were applied to a historical cohort of women with induction of labor at two Norwegian tertiary hospitals in the period January 1, through July 31, 2021. The criteria included low-risk women with an unscarred uterus expecting a healthy, singleton baby in cephalic position at term. The primary outcome was the proportion of women eligible for outpatient labor induction. Secondary outcomes included reasons for ineligibility and, for eligible women, safety and efficacy outcomes.

Results: Overall, 29.7% of the 1320 women who underwent labor induction in a singleton term pregnancy met the criteria for outpatient labor induction. We identified two serious adverse events that potentially could have occurred outside the hospital if the women had received outpatient care. The mean duration from initiation of labor induction to administration of the last misoprostol was 22.4 h. One in 14 multiparous women gave birth within 3 h after the last misoprostol dose.

Conclusions: In this historical cohort, three in ten women met the criteria for outpatient management of labor induction with oral misoprostol. Serious adverse events were rare. The average time span from the initiation of labor induction to the last misoprostol was nearly 24 h. This suggests a potential for low-risk women with an induced labor to spend a substantial period of time at home before labor onset. However, larger studies testing or evaluating labor induction with oral misoprostol as an outpatient procedure are needed to draw conclusions.

Keywords: birth; induction of labor; maternity care; misoprostol; obstetrics; outpatient labor induction.

FIGURE 1

Eligibility criteria for outpatient labor induction in the LINO project.

FIGURE 2

Flow chart of included women and women eligible for outpatient labor induction.

FIGURE 3

Main indication for induction of labor among women eligible for outpatient labor induction. “Other” includes hypertension not requiring monitoring, oligohydramnios with amniotic fluid index <3.5 cm, mild intrahepatic cholestasis, not medically treated gestational diabetes mellitus.

FIGURE 4

Stacked bar of median hours of the stages in the labor induction processes. (A) Induction of labor with Foley catheter and misoprostol, (B) Induction of labor with misoprostol without Foley catheter. TGCS group 2a, nulliparous with a term singleton cephalic fetus; TGCS group 4a, multiparous with a term singleton cephalic fetus without previous cesarean section.