Luteinizing hormone-follicle stimulating hormone ratio as biological predictor of post-partum depression

Post-partum depression (PPD) is the common adverse outcome of child bearing which affects the wellbeing of both mother and newborn and has long-term effects. Hence, reliable potential biological tests for early detection of PPD are essential. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) were associated with depressive disorders and the present study estimated the levels of serum FSH, LH in postpartum depression and explored them as predictive biomarkers in the development of PPD.

In this nested case control study done at a tertiary care hospital in South India, 450 postpartum women were screened at 6th week post-delivery for PPD. Socio-demographic and clinical data were recorded and depressive symptoms were assessed using Edinburgh Postnatal Depression Scale (EPDS). Out of 450 subjects screened, 100 women with depressive symptoms were categorized as cases and 100 controls were selected from the remaining subjects matching for age and BMI with cases. Serum levels of FSH and LH were measured using direct competitive immunoassay by chemiluminescene technology.

Serum LH/FSH ratio was found to be significantly (p=0.02) low in PPD women when compared to normal postpartum subjects. We also found a significant negative correlation between LH/FSH ratio and EPDS scores. Based on the receiver operating characteristic curve, the optimal cut-off value for serum of LH/FSH levels in predicting postpartum depression was estimated to be 0.22mlU/mL with an AUC of 0.598 (95%CI, 0.291-0.859).

Our study demonstrated that low LH/FSH ratio after delivery was associated with increased risk for the development of PPD. Low LH/FSH ratio at six-week post delivery can be used as a robust biochemical predictor of post-partum depression.