Objective: To estimate the association between common mental disorders (CMD) during pregnancy and risk of low birth weight (LBW) or preterm birth (PTB).
Methods: A prospective cohort study was conducted with 831 pregnant women from antenatal clinics in primary healthcare in São Paulo, Brazil. The clinical interview schedule-revised and demographic questionnaires were administered between the 20th and 30th weeks of gestation. Information on infant weight and gestational age at birth were obtained from hospital records. Univariate analyses were used to examine the association between the main exposure and main outcomes. Statistical associations were examined with χ(2) tests. Adjusted odds ratios (OR) and 95% confidence intervals (CI) for the main outcomes were obtained using a multivariable logistic regression model.
Results: The prevalence of CMD during gestation was 33.6 (95% CI: 30.4-36.9). The follow-up rate was 99.5%. Sixty three (7.6%) newborns were classified as LBW and 56 (6.9%) were classified as PTB. CMD during pregnancy was not associated with risk of PTB (adjusted OR:1.03, 95% CI: 0.57-1.88) or LBW (adjusted OR:1.09, 95% CI: 0.62-1.91).
Conclusions: CMD prevalence is high among low-income and low-risk pregnant women attended by public health services in a middle-income country, but not confer an increased risk for adverse obstetric outcome.