Primary outcomes
The primary outcome of interest was PTSD in the postnatal period, defined as the six months following giving birth. The diagnosis of PTSD should have been based on DSM criteria, using either the Impact of Event Scale (IES) or another validated scale used by study authors. Data on symptoms of PTSD which did not meet full criteria for a diagnosis of PTSD were also included, as not all women participating in the studies selected had undergone a full diagnostic interview. Qualitative data were included which described the attitudes and experiences towards different modes of birth by women who developed postnatal PTSD and those who supported them.