Current estimates of the prevalence of depression during pregnancy vary widely. A
more precise estimate is required to identify the level of disease burden and develop
strategies for managing depressive disorders. The objective of this study was to estimate
the prevalence of depression during pregnancy by trimester, as detected by validated
screening instruments (ie, Beck Depression Inventory, Edinburgh Postnatal Depression
Score) and structured interviews, and to compare the rates among instruments.
Observational studies and surveys were searched in MEDLINE from 1966, CINAHL from
1982, EMBASE from 1980, and HealthSTAR from 1975.
A validated study selection/data extraction form detailed acceptance criteria. Numbers
and percentages of depressed patients, by weeks of gestation or trimester, were reported.
Two reviewers independently extracted data; a third party resolved disagreement. Two
raters assessed quality by using a 12-point checklist. A random effects meta-analytic
model produced point estimates and 95% confidence intervals (CIs). Heterogeneity was
examined with the chi(2) test (no systematic bias detected). Funnel plots and Begg-Mazumdar
test were used to assess publication bias (none found). Of 714 articles identified,
21 (19,284 patients) met the study criteria. Quality scores averaged 62%. Prevalence
rates (95% CIs) were 7.4% (2.2, 12.6), 12.8% (10.7, 14.8), and 12.0% (7.4, 16.7) for
the first, second, and third trimesters, respectively. Structured interviews found
lower rates than the Beck Depression Inventory but not the Edinburgh Postnatal Depression
Scale.
Rates of depression, especially during the second and third trimesters of pregnancy,
are substantial. Clinical and economic studies to estimate maternal and fetal consequences
are needed.