Maternal serum activin A, inhibin A, and follistatin in pregnancies with appropriately grown and small-for-gestational-age fetuses classified by umbilical artery Doppler ultrasound.

Abstract

The purpose of this study was to examine the relationship of maternal serum activin A, inhibin A, and follistatin with fetal growth and placental function. Inhibin A, activin A, and follistatin were measured in maternal serum that was stored from normally grown (control subjects, n = 50) and small-for-gestational-age pregnancies (n = 49), prospectively classified as normal small-for-gestational-age pregnancy or fetal growth-restricted pregnancy with the use of umbilical artery Doppler ultrasound. Activin A and inhibin A were significantly increased in fetal growth-restricted pregnancies compared with control subjects (activin A: regression coefficient, 0.54, P <.001; inhibin A: regression coefficient, 0.47, P =.003). The activin:follistatin ratio was significantly higher in fetal growth-restricted pregnancies compared with control subjects (P <.001). There were no significant differences between analyte levels of normal small-for-gestational-age pregnancies and control subjects. Maternal serum activin A, inhibin A, and activin:follistatin ratio are raised in fetal growth-restricted pregnancies but not in normal small-for-gestational age pregnancies. This provides further evidence of the difference between subgroups within small-for-gestational-age pregnancies and emphasizes the need to stratify for this in research.