Objective: To quantify the rate of maternal complications associated with a periviable birth in a contemporary population of live births in the state of Ohio.
Methods: We conducted a population-based retrospective cohort study of all live births in Ohio (2006-2015). Maternal, obstetric, and neonatal characteristics were compared between women who delivered in the periviable period (20-25 weeks of gestation) with those who delivered preterm (26-36 weeks of gestation) and at term (greater than 36 weeks of gestation). Women were also stratified by 3-week gestational age epochs (ie, 20-22, 23-25 weeks of gestation). The primary study outcome was a composite of individual adverse maternal outcomes (chorioamnionitis, blood product transfusion, hysterectomy, unplanned operation, and intensive care unit [ICU] admission). Multivariate logistic regression estimated the relative association of periviable birth with maternal complications.
Results: Of 1,457,706 live births in Ohio during the 10-year study period, 6,085 live births (0.4%) occurred during the periviable period (20-25 weeks of gestation). The overall rate of the composite adverse outcome was 17.2%. In multivariate analysis, periviable birth was associated with an increased risk of the composite adverse maternal outcome (adjusted relative risk [RR] 5.8, CI 5.4-6.2) and individual complications including transfusion (adjusted RR 4.4, CI 3.4-5.7), unplanned operative procedure (adjusted RR 2.0, CI 1.7-2.4), unplanned hysterectomy (adjusted RR 7.8, CI 4.6-13.0), uterine rupture (adjusted RR 7.1, CI 3.8-13.4), and ICU admission (adjusted RR 9.6, CI 7.2-12.7) compared with the term cohort. Delivery between 20-22 weeks and 23-25 weeks of gestation was associated with the highest risk of composite adverse outcome. The risk of composite adverse outcome decreased with advancing gestational age stratum.
Conclusion: Periviable birth is associated with significant maternal morbidity. Nearly one in five women in this cohort had a serious morbidity associated with their periviable delivery.