Induction of labour in women with an unfavourable cervix is associated with a risk of caesarean delivery. When a diagnosis of fetal growth restriction (FGR) is also involved, the risk of intrapartum fetal acidosis increases. The main objective was to identify prognostic factors for the risk of caesarean delivery after induction for suspected FGR after 36 weeks of gestation with an unripe cervix.

This was a retrospective, single-centre (Port Royal, Paris, France) study of women with a singleton fetus in cephalic presentation, with labour induced at or after 36 weeks for suspected FGR diagnosed during second or third trimester of pregnancy with an unripe cervix (Bishop score under 6) who gave birth between 1 January 2015 and 31 December 2019. A multivariable analysis was performed to identify the factors related to an increased risk of caesarean section.

Of the 146 women included, 56 (38.4%) had caesarean deliveries. After adjustment, the factors significantly associated with the risk of caesarean were maternal age greater than 39 years (ORa = 4.33 [1.22-17.2], reference: 25-39 years), nulliparity (ORa = 3.49 [1.25-11.2]), and an abnormal fetal umbilical artery Doppler velocimetry (ORa = 3.50 [1.47-8.70]). The risk of poor neonatal condition did not differ significantly between women with vaginal and caesarean deliveries (2.3% vs 7.3%, P = 0.21).

When FGR is suspected at 36 weeks of gestation and later, induction of labour is a reasonable option, even if the cervix is unripe, as the risk of caesarean delivery appears acceptable and neonatal status is good and similar with both modes of delivery.