Objective: We systematically review evidence on the prevalence and incidence of perinatal depression and compare these rates with those of depression in women at non-childbearing times.
Data sources: We searched MEDLINE, CINAHL, PsycINFO, and Sociofile for English-language articles published from 1980 through March 2004, conducted hand searches of bibliographies, and consulted with experts.
Methods of study selection: We included cross-sectional, cohort, and case-control studies from developed countries that assessed women for depression during pregnancy or the first year postpartum with a structured clinical interview.
Tabulation, integration, and results: Of the 109 articles reviewed, 28 met our inclusion criteria. For major and minor depression (major depression alone), the combined point prevalence estimates from meta-analyses ranged from 6.5% to 12.9% (1.0-5.6%) at different trimesters of pregnancy and months in the first postpartum year. The combined period prevalence shows that as many as 19.2% (7.1%) of women have a depressive episode (major depressive episode) during the first 3 months postpartum; most of these episodes have onset following delivery. All estimates have wide 95% confidence intervals, showing significant uncertainty in their true levels. No conclusions could be made regarding the relative incidence of depression among pregnant and postpartum women compared with women at non-childbearing times.
Conclusion: To better delineate periods of peak prevalence and incidence for perinatal depression and identify high risk subpopulations, we need studies with larger and more representative samples.