Activin A and follistatin in menstrual blood: Low concentrations in women with dysfunctional uterine bleeding

Activin A and follistatin are growth factors produced by several organs, comprising the endometrium, where they modulate cell and tissue differentiation. In this study, the authors tested whether active A and follistatin are measurable in menstrual blood and whether their concentration change in women with dysfunctional uterine bleeding (DUB). The authors evaluated health women with regular menstrual cycles (n = 15) and women with DUB (n = 12). Active A and follistatin were measured in both menstrual and peripheral blood samples using highly sensitive enzyme immunoassays, whereas their respective mRNAs were quantified by real-time polymerase chain reaction in endometrial samples collected during the perimenstrual period. Active A concentration were 4-fold higher in menstrual than collected during the perimenstrual period. Activin A concentration were 4-fold higher in menstrual than in peripheral serum of healthy women (mean +/- SE, 4.24 +/- 0.18 vs 1.00 +/- 0.15 ng/mL, P < .001) and were significantly lower in women with DUB compared to healthy subjects (P < .001). Follistatin concentration was 8-fold higher in menstrual than in peripheral serum of healthy women (3.94 +/- 0.49 vs 0.49 +/- 0.04 ng/mL, P < .001) and was significantly lower in the menstrual serum of women with DUB compared to controls (P < .001). There was correlation between menstrual and peripheral serum concentration of both proteins. The endometrial expression of active A and follistatin are measurable in high concentration in human menstrual blood and are relatively lower in women with DUB. The quantitative assessment of active A and follistatin in menstrual serum might be a putative clinical marker of endometrial function.