To assess the empirical basis of prevalence and risk factors of childbirth-related posttraumatic stress symptoms and PTSD in mothers, the relevant literature was critically reviewed. A MEDLINE and PSYCHLIT search using the key words "posttraumatic stress", "PTSD", "childbirth" and "traumatic delivery" was performed. The generated list of articles was supplemented by a review of their bibliographies. A total of 31 articles was selected. The primary inclusion criterion was report of posttraumatic stress symptoms or PTSD specifically related to childbirth. Case studies and quantitative studies on regular childbirth and childbirth by emergency cesarean section were identified. Consistency among studies was found with regard to development of posttraumatic stress symptoms as a consequence of traumatic delivery. Methodological issues concerning prevalence and risk factors were discussed. Case studies and quantitative studies confirm that childbirth may be experienced as so emotionally intense that it can lead to the development of posttraumatic stress symptoms or even a PTSD-profile. Among the identified risk factors were a history of psychological problems, trait anxiety, obstetric procedures, negative aspects in staff-mother contact, feelings of loss of control over the situation, and lack of partner support. The conclusion of the current review is twofold. First, traumatic reactions to childbirth are an important public health issue. Secondly, studying childbirth offers opportunity to prospectively study the development of posttraumatic stress reactions.