Various studies have observed an association between history of abuse and increased risk for perinatal depression.  The data regarding childhood sexual abuse (CSA) in particular have been less consistent.  A recent review of the literature attempts to better understand the relationship between CSA and risk for depression during pregnancy and the postpartum period.

The findings suggest that a history of childhood sexual abuse may be more strongly associated with depression or depressive symptoms during pregnancy than with postpartum depression.  The authors’ literature search identified  seven eligible studies on the antenatal period and another seven on the postpartum period. All but one of the antenatal studies observed statistically significant positive associations between CSA and depression or depressive symptoms during pregnancy.  Pooling the results of the various studies, the unadjusted and adjusted odds ratios were 1.82 (95 % confidence interval (CI) 0.92, 3.60) and 1.20 (95 % CI 0.81, 1.76).  The studies yielded inconsistent findings regarding the impact of CSA and risk for postpartum depression.  

While the association between CSA and antenatal depression is statistically significant, it it is relatively small, with an adjusted odds ratio of 1.2.  But looking more closely at some of the individual reports included in this review, it appears that the association between CSA and perinatal depression may be stronger in certain populations.

For example, if we look at the study from Robertson-Blackmore and colleagues which included 374 pregnant women (aged 20-34 years) from a predominantly low-income, inner-city population, the results are somewhat different.  In this study, 39% of the sample reported at least one traumatic event; antennal (but not postpartum) depression was predicted by trauma history (odds ratio [OR] = 2.16; 95% CI, 1.31-3.54) and, in particular, experiencing childhood sexual abuse (OR = 2.47; 95% CI, 1.27-4.78).  The researchers observed a distinct dose-response effect of trauma on risk for antenatal depression; women who experienced 3 or more traumatic events had a 4-fold risk of antenatal depression (OR = 4.34; 95% CI, 2.16-8.70) of compared to women with no trauma history.  This is an especially important finding in that women living in inner city or impoverished environments often experience multiple traumatic events which may render them more vulnerable to depression than women in other settings.

As to why childhood sexual abuse appears to modulate risk for antenatal depression more than postpartum depression is an interesting question.  The authors offer several possible explanations.   It is well-established that women with histories of childhood trauma have long-term alterations in concentrations of corticotropin-releasing hormone (CRH) and cortisol, glucocorticoid hormones released by the hypothalamic-pituitary-adrenal (HPA) axis. In this population with dysregulation of the HPA axis, the neuroendocrine changes that take place during pregnancy, specifically increasing levels of CRH, may have a negative impact on mood.  In addition, some investigators have noted that in women with histories of sexual abuse, procedures associated with routine pregnancy care and labor and delivery may experience memories of their abuse and thus may be more vulnerable to depression.

Perhaps this report raises more questions than it resolves; however, it does point to the need for more research on the effects of childhood trauma on risk for perinatal depression.  The authors remark,

 

“Given the significance of the topic, noted gaps and limitations of the available evidence, and the high prevalence of CSA and depression among women globally, we maintain that large multinational longitudinal studies with systematic exposure and outcome assessment are needed to provide higher-quality information about the incidence and progression of depressive symptoms and depression in prenatal and postpartum women given history of early life stressors, access to social support, and other buffers of stress across the life course. In addition, there is need for studies that incorporate biochemical and molecular risk markers that will facilitate exploration of mechanistic hypotheses and prognostic indicators of morbidity and response to treatment. Finally, given that all available studies were conducted in high-income countries, studies examining the implications of the CSA-depression relationship in middle- and low-income countries are needed.”

Ruta Nonacs, MD PhD

Robertson-Blackmore E, Putnam FW, Rubinow DR, et al.  Antecedent trauma exposure and risk of depression in theperinatal period.  J Clin Psychiatry. 2013 Oct;74(10):e942-8.

Wosu AC, Gelaye B, Williams MA.   History of childhood sexual abuse and risk of prenatal and postpartum depression or depressive symptoms: an epidemiologic review.  Arch Womens Ment Health. 2015 May 10. [Epub ahead of print]