Abstract BACKGROUND A range of opinions exist in the literature regarding obstetric management of pregnant women with Chiari malformation type I (CM-I). OBJECTIVE To examine obstetrical practices and outcomes with childbirth of women with CM-I. METHODS We examined insurance claims data from a large, privately insured health care network and identified admissions for childbirth from 2004 to 2014. Women with a diagnosis of CM-I as well as normal controls were analyzed for demographic characteristics, type of obstetric management, and complications of childbirth. RESULTS We identified 866 patients with CM-I diagnosis who had 1048 hospitalizations for delivery, including 103 deliveries to 83 patients who underwent performance of CM-I decompression (CMD) either before or after childbirth. Among 400 births that occurred after CM-I diagnosis, rates of caesarean section (C-section) were higher (42.3% vs 36.2%, OR 1.29, 95% CI 1.00-1.66, P = .05) and rates of epidural analgesia were lower (45.3% vs 55.4%, OR 0.67, 95% CI 0.52-0.85, P = .001) compared to 648 births before CM-I diagnosis. The rate of serious maternal morbidity was similar among deliveries to women with CM-I diagnosis (both before and after delivery) compared to 11 000 normal controls. CONCLUSION A diagnosis of CM-I prior to delivery is associated with a higher rate of C-section and a lower rate of epidural analgesia. Rates of serious maternal morbidity among women with CM-I were similar to those for normal controls. The data suggest a predelivery diagnosis of CM-I may influence obstetric decisions despite no evidence of substantially increased delivery risk in this group.