Objective: The overall annual incidence rate of caesarean delivery in the United States has been steadily rising since 1996, reaching 32.9% in 2009. Primary cesareans often lead to repeat cesareans, which may lead to placenta previa and placenta accreta. This study's goal was to forecast the effect of rising primary and secondary cesarean rates on annual incidence of placenta previa, placenta accreta, and maternal mortality.
Methods: A decision-analytic model was built using TreeAge Pro software to estimate the future annual incidence of placenta previa, placenta accreta, and maternal mortality using data on national birthing order trends and cesarean and vaginal birth after cesarean rates. Baseline assumptions were derived from the literature, including the likelihood of previa and accreta among women with multiple previous cesarean deliveries.
Results: If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years.
Conclusions: If cesarean rates continue to increase, the annual incidence of placenta previa, placenta accreta, and maternal death will also rise substantially.