To assess the prevalence of posttraumatic stress disorder (PTSD) symptoms and identify characteristics associated with it 2 months after singleton vaginal delivery at or near term. We conducted an ancillary cohort study of the TRAAP (TRAnexamic Acid for Preventing postpartum hemorrhage after vaginal delivery) randomized controlled trial in 15 French hospitals in 2015-2016. Women who had singleton vaginal delivery after 35 weeks of gestation were enrolled. After randomization, characteristics of labor and delivery were prospectively collected and paid special attention to postpartum blood loss. Posttraumatic stress disorder profile and provisional diagnosis were assessed 2 months after childbirth by two self-administered questionnaires: the IES-R (Impact of Event Scale-Revised) and the TES (Traumatic Event Scale). Associations between potential risk factors and PTSD symptoms were analyzed by multivariable logistic or linear regression modeling, depending on the type of dependent variable. Questionnaires were returned by 2,740 of 3,891 women for the IES-R and 2,785 of 3,891 women for the TES (70.4% and 71.6% response rate). The prevalence of PTSD symptoms was 4.9% (95% CI 4.1-5.8%; 137/2,785) with the TES, and the prevalence of PTSD provisional diagnosis was 1.6% (95% CI 1.2-2.1%; 44/2,740), with the IES-R and 0.4% (95% CI 0.2-0.8%; 9/2,080) with the TES. Characteristics associated with a higher risk of PTSD in multivariable analysis were vulnerability factors - notably migrant status and history of psychiatric disorder (adjusted odds ratio [aOR] 2.7 95% CI 1.4-5.2) - and obstetric factors - notably induced labor (aOR 1.5 95% CI 1.0-2.2), being labor longer than 6 hours (aOR 1.7 95% CI 1.1-2.5), postpartum hemorrhage of 1,000 mL or more (aOR 2.0 95% CI 1.0-4.2), and bad memories of delivery at day 2 postpartum (aOR 4.5 95% CI 2.4-8.3) as assessed with the IES-R. Results were similar with the TES. Approximately 1 of 20 women with vaginal delivery have PTSD symptoms at 2 months postpartum. History of psychiatric disorder, postpartum hemorrhage, and bad memories of deliveries at day 2 were the main factors associated with a PTSD profile.