Maternal complications in settings where two-thirds of extremely preterm births are delivered by cesarean section

To investigate the maternal complications associated with cesarean section (CS) in the extremely preterm period according to the gestational week (GW) and to indication of delivery.

This is a retrospective case-referent study with a review of medical records of women who delivered at 22-27 weeks of gestation (n=647) at two level III units in Sweden. For abdominal delivery, gestational length was stratified into 22-24 (n=105) and 25-27 (n=301) weeks. For comparison, data on women who underwent a CS at term were identified in a register-based database.

The rate of CS in extremely preterm births was 62.8%. There was no difference in the complication rates, but types of incisions other than the low transverse incision were required more often at 22-24 (18.1%) weeks than at 25-27 GWs (9.6%) (P=0.02). Major maternal complications occurred in 6.6% compared with 2.1% in the extremely preterm and term CS, respectively (P<0.01). A maternal indication of extremely preterm CS increased the risk of complications.

Almost two-thirds of the births at 22-27 GWs had an abdominal delivery. No increase in short-term morbidity was observed at 22-24 weeks compared to 25-27 weeks. CS performed extremely preterm had more major complications recorded than cesarean at term. The complications are driven by the underlying maternal condition.