The association between prepregnancy obesity and screening positive for postpartum depression

To describe the association between reported prepregnancy body mass index (BMI) and screening positive for depression.

Cohort study.

Four urban hospitals in Utah, USA.

Women delivering a term, singleton, live-born infant at one of four urban hospitals in Utah in the period 2005-2007.

Women were enrolled immediately postpartum. Demographic, anthropometric, stressors, psychiatric, and medical/obstetric and family-history data were obtained. Prepregnancy height, weight, and pregnancy weight gain were self-reported. The primary exposure variable, prepregnancy BMI, was calculated. Women were stratified into the six World Health Organization BMI categories (underweight, normal weight, pre-obese, or obese class 1-3).

At 6-8 weeks postpartum, women were screened for depression using the Edinburgh Postnatal Depression Scale (EPDS). The primary outcome measure was a prespecified EPDS score of > or =12.

Among the 1053 women studied, 14.4% of normal weight women screened positive for postpartum depression. This proportion was greater in women classed as underweight (18.0%, n = 11), pre-obese (18.5%, n = 38), obese class 1 (18.8%, n = 16), obese class 2 (32.4%, n = 11), and obese class 3 (40.0%, n = 8) (P < 0.01). Controlling for demographic, psychological, and medical/obstetric factors, prepregnancy class-2 (aOR 2.87, 95% CI 1.21-6.81) and class-3 (aOR 3.94, 95% CI 1.38-11.23) obesity remained strongly associated with screening positive for postpartum depression, compared with women of normal weight.

Self-reported prepregnancy obesity may be associated with screening positive for depression when measured postpartum.