Abstract
OBJECTIVE: We reviewed studies of maternal depression and preterm birth (PTB), low birthweight (LBW) and small-for-gestational-age (SGA) in the context of methodological differences between studies and potential limitations. METHODS: We conducted a literature search of PubMed (1996-2011) for English-language studies of maternal depression and (1) PTB and gestational age (GA), (2) LBW and birthweight (BW) and (3) SGA. Thirty-six studies met eligibility criteria. RESULTS: Elevated depression levels, particularly in early- to mid-pregnancy, appear to increase risk of PTB and SGA. Findings suggest an increased risk for LBW, but were less consistent. Methodological differences and limitations likely contributed to conflicting findings. A wide range of depression measures were used with the majority of studies utilizing measures not designed, or validated, for pregnant women. Studies failed to assess depression at multiple pregnancy time points, thus constraining the ability to assess the impact of duration and pattern of exposure to depression. Antidepressant use and co-morbid psychosocial factors were rarely considered as potential confounders or effect modifiers. CONCLUSIONS: Studies suggest that depression during pregnancy may be an important risk factor for PTB and SGA, and possibly LBW. Improved study methodology is needed to elucidate the consequence of maternal depression on adverse birth outcomes.