Are female children more vulnerable to the long-term effects of maternal depression during pregnancy?

BACKGROUND: Female fetuses are more vulnerable to high levels of maternal glucocorticoids. We examined whether exposure to prenatal maternal depression, a condition associated with high glucocorticoids, carries greater risk for depression at 12 and 18 years in girls.

METHODS: Our sample comprised 7959 mothers and children from the Avon Longitudinal Study of Parents and Children following imputation for missing data. Maternal depression was assessed pre-and post-natally, and offspring depression at ages 12 and 18. We used logistic regression models to examine the relationship between exposure to prenatal and postnatal depression and offspring depression at 18 and 12 and interactions with gender.

RESULTS: There was an interaction between prenatal depression and gender (P=0.027) and between postnatal depression and gender (P=0.027) for offspring depression at 18. Following adjustment in pre-natally depressed mothers, the odds ratio for offspring depression at 18 was 1.55 (95% c.i. 1.03-2.34) for girls and 0.54 (0.23-1.26) for boys. In post-natally depressed mothers, the odds ratio for offspring depression at 18 was 1.15 (0.70-1.89) in girls and 3.13 (1.52-6.45) in boys. However there was no evidence for interaction between prenatal or postnatal depression and gender (P=0.559 and 0.780 respectively) for offspring depression at 12.

LIMITATIONS: As expected with this large cohort spanning over 18 years, there was loss-to-follow-up.

CONCLUSIONS: This is the first evidence in humans that increased vulnerability of female fetuses to maternal stress responses during pregnancy persists into adolescence. One explanation for gender differences emerging later is more depressive symptomatology is attributed to heritable risk at 12, whereas biological processes involved in brain development at 18 may be influenced by foetal programming. If replicated, this study has potential to help understand intergenerational transmission of depression, a leading cause of morbidity worldwide.