Placental and maternal serum inhibin A in patients with preeclampsia and small-for-gestational-age

Aim: The purpose of this study was to determine the levels of inhibin A simultaneously in the maternal serum and placental extract in preeclampsia (PE) with or without small-for-gestational-age (SGA) and normal controls at term, and to evaluate the relationship among changes in serum and placental inhibinA according to the severity of PE and PE with or without SGA. Material and Methods: This study involved 40 pregnant women; normal (n = 20), and PE (n = 20), the latter of who were classified into (i) mild (n = 10) and severe PE (n = 10); (ii) PE with SGA (n = 7) and without SGA (n = 13). Inhibin A concentrations were quantified by enzyme-linked immunosorbent assay (ELISA) in the maternal serum and placental extract. Inhibin-a subunit in the placenta was stained by immunohistochemistry (IHC), and its intensity was graded by a semiquantitative scoring method. Results: There was a positive correlation in inhibin A concentrations between the serum and placental extract (r = 0.57, P < 0.001). Both maternal serum and placental inhibin A in PE groups were significantly higher than in controls, but there was no severity-dependent increase of inhibin A when compared with mild and severe PE. There was no difference in inhibin A levels between PE with and without SGA. Moreover, the inhibin-a subunit was predominantly abundant in the cytoplasm of the syncytiotrophoblasts, where the PE groups showed higher staining intensity than the controls (P < 0.000). Conclusion: Serum inhibin A level might be a useful biomarker for diagnosis and monitoring of PE.