Antenatal diet quality and perinatal depression: the Microbiome Understanding in Maternity Study (MUMS) cohort.

Background: Previous findings from research investigating the role of antenatal nutrition in preventing postpartum depression (PPD) are inconsistent. Our primary aim was to investigate the association between pregnancy diet quality and PPD. Our secondary aim was to investigate associations between (a) diet quality and depression during pregnancy and (b) depression during pregnancy and PPD.

Methods: This analysis represents data from 73 women participating in the Microbiome Understanding in Maternity Study (MUMS) cohort in Sydney, Australia, which followed women from Trimester 1 of pregnancy to 1-year postpartum (PP). Participants' diet quality was assessed using the Australian Eating Survey at Trimester 1 and 3 to calculate diet quality, known as the Australian Recommended Food Score (lower diet quality defined as score <39; higher diet quality ≥39). Depression was assessed using the Edinburgh Depression Scale at Trimesters 1, 2, 3 and 6 weeks PP (defined as score ≥11).

Results: Depression scores during pregnancy were significantly associated with depression score 6 weeks PP (Trimester 1: r = 0.66, Trimester 2: r = 0.69, Trimester 3: r = 0.67; all p < 0.001). Diet quality during pregnancy was not significantly correlated with 6-week PPD score. In unadjusted analysis, diet quality during pregnancy was not associated with pregnancy depression scores. When adjusted for age, parity and Trimester 1 body mass index, Trimester 1 physical activity levels and gestational weight gain, higher Trimester 3 diet quality was associated with reduced Trimester 3 depression only.

Conclusions: Depression scores during pregnancy were positively associated with PPD, highlighting the importance of screening for depression during pregnancy and postnatally. Larger longitudinal prospective studies may elucidate the association between diet quality and PPD.