Objective To estimate the prevalence of post-traumatic stress disorder (PTSD) after childbirth in a group of postpartum Nigerian women and to examine any associated factors.Design A cross-sectional survey.Setting Postnatal clinics and infant immunisation clinics of the five health centres in Ilesa Township, Nigeria.Population A total of 876 women at 6 weeks postpartum.Methods The postpartum women were assessed for PTSD at 6 weeks. Other data collected were demographic characteristics, details of pregnancy and delivery and neonatal outcome. Additionally, the following measures were used: the MINI International Neuropsychiatric Interview to assess PTSD, the Index of Marital Satisfaction to measure the degree of problem a spouse encounters in the marital relationship, the Medical Outcome Study Social Support Survey to measure social support, the Life Events Scale to measure the life stress covering the preceding 12 months and the Labour Agentry Scale that measures the maternal experiences of control during childbirth.Main outcome measures Prevalence of PTSD in this population of postpartum Nigerian women, and how this prevalence related to other maternal and neonatal characteristics.Results The prevalence of PTSD was 5.9%. The factors independently associated with PTSD after childbirth include hospital admission due to pregnancy complications (OR 11.86, 95% CI 6.36-22.10), instrumental delivery (OR 7.94, 95% CI 3.91-16.15), emergency caesarean section (OR 7.31, 95% CI 3.53-15.10), manual removal of placenta (OR 4.96, 95% CI 2.43-10.14) and poor maternal experience of control during childbirth (OR 5.05, 95% CI 2.69-9.48).Conclusions The prevalence of PTSD after childbirth in Nigerian women is slightly higher than those found in western culture. An effective model for the prediction of the development of PTSD after childbirth needs to be developed and evaluated, and interventions aimed at reducing the incidence of PTSD after childbirth need further research.Keywords Caesarean section, cross-culture, postpartum, post-traumatic stress disorder, trauma.Please cite this paper as: Adewuya A, Ologun Y, Ibigbami O. Post-traumatic stress disorder after childbirth in Nigerian women: prevalence and risk factors.