Strengths and Limitations
The principal strengths of the present study are the prospective, multicenter design and the size of the sample. To the best of our knowledge, this is the largest sample to date to examine the determinants of PPD prospectively, with a good overall response rate at 1 year. In addition, all psychiatric diagnoses are based on a rigorous clinical assessment using DSM-5- criteria. Moreover, the evaluations at 8 weeks and then at 1 year postpartum make it possible to distinguish 2 types of PPD, with different determinants for early and late PPD. Finally, IGEDEPP provides an extensive assessment of a wide range of determinants, including socio-demographic characteristics, personal and family history of psychiatric disorders, childhood trauma, as well as stressful life events during pregnancy and postpartum, whether related to pregnancy or not.
A main limitation of the study is the fact that all included women were Caucasian, due to the original objective of the cohort: studying genetic determinants of PPD. The women included also had a high level of education and favorable socio-economic conditions. However, the prevalence of postpartum depression as well as prevalence of the psychiatric disorders assessed were consistent with other samples of women, as discussed elsewhere (29).