Prenatal Growth Affects Serum Inhibin B Levels in Male Infants Until 18 Months of Postnatal Age

The current study was undertaken to examine the correlation between serum levels of inhibin A or inhibin B and prenatal growth. The study population consisted of 53 infants born at 25-30 weeks gestation and weighing 400-3060g (29 boys and 24 girls) . Serum inhibin A and inhibin B were determined by sandwich enzyme-linked immunosorbent assay (ELISA) at 1-18 postnatal months of age. To assess the independent association of serum inhibin A and inhibin B with all other evaluated variables, we used a backward stepwise multiple regression analysis. Independent variables were postnatal age, body weight standard deviation (SD) score at blood sampling, gestational age, birth weight and its SD score for gestational age. In male infants, birth weight SD score and postnatal months of age were associated with inhibin B concentration after adjustment for other factors (β = 0.331, P = 0.044; β = -0.513, P = 0.03) . The serum levels of inhibin B in female infants were negatively correlated with postnatal age (β = -0.524, P < 0.01) . On the other hand, there was no relationship between inhibin A and any variable of prenatal growth. These results suggest that postnatal inhibin B secretion in male infants may be affected by prenatal growth.