Morbidity following primary cesarean delivery in the Danish National Birth Cohort

OBJECTIVE: Cesarean delivery rates are on the rise in many countries, including the United States. There is mounting evidence that cesarean delivery is associated with adverse reproductive outcomes in subsequent pregnancies. The purpose of this article is to review those outcomes in a well-defined cohort of pregnant women. STUDY DESIGN: In a cohort of primigravid women from the Danish National Birth Cohort with known baseline exposure characteristics, we stratified women by method of first delivery, vaginal or cesarean, and evaluated for appearance of adverse reproductive events in subsequent pregnancies. RESULTS: After adjusting for age, body mass index, alcohol, smoking, and socioeconomic status, women who underwent cesarean delivery at first birth were at increased risk in their subsequent pregnancy for anemia (odds ratio [OR], 2.8; 95% confidence interval [CI], 2.3-3.4), placental abruption (OR, 2.3; 95% CI, 1.5-3.6), uterine rupture (OR, 268; 95% CI, 65.6-999), and hysterectomy (OR, 28.8; 95% CI, 3.1-263.8). CONCLUSION: Women who deliver their first baby with a cesarean are at increased risk of adverse reproductive outcomes in subsequent pregnancies and should be counseled accordingly.