Objective This study aimed to examine whether prenatal low-dose aspirin (LDA) therapy affects risk of cesarean versus vaginal delivery. Study Design This study is a secondary analysis of the randomized clinical effects of aspirin in gestation and reproduction (EAGeR) trial. Women received 81-mg daily aspirin or placebo from preconception to 36 weeks of gestation. Mode of delivery and obstetric complications were abstracted from records. Log-binomial regression models estimated relative risk (RR) of cesarean versus vaginal delivery. Data were analyzed among the total preconception cohort, as well as restricted to women who had a live birth. Results Among 1,228 women, 597 had a live birth. In the intent-to-treat analysis, preconception-initiated LDA was not associated with risk of cesarean (RR = 1.02; 95% confidence interval [CI]: 0.98–1.07) compared with placebo. Findings were similar in just women with a live birth and when accounting prior cesarean delivery and parity. Conclusion Preconception-initiated daily LDA was not associated with mode of delivery among women with one to two prior losses. Key Points Aspirin was not associated with risk of cesarean section. Aspirin was not associated with mode of delivery. No increased risk of bleeding with use of aspirin. [ABSTRACT FROM AUTHOR]