Circulating levels of inhibin A, inhibin B and activin A in normal and intrauterine growth restricted (IUGR) fetuses

Objective: To evaluate the relationships between circulating levels of inhibin A, inhibin B and activin A, and sex, gestational age and gonadotropins in normal and pathological fetuses. Study design: The study included 31 normal fetuses and 12 affected with intrauterine growth restriction (IUGR) of gestational age ranging 20-40 weeks. Results: No gender difference in inhibin A and activin A levels were observed. Inhibin B levels were significantly higher in males than in females (P < 0.05). Fetuses with the highest levels of inhibin A and B were found in the IUGR group that also showed activin A levels significantly higher than normal. No correlations were observed between inhibin A, inhibin B, activin A and both gonadotropins. Conclusion: Plasma inhibin A, inhibin B and activin A are detectable in both genders during intrauterine life. The different gender pattern of inhibin B suggests that inhibin B may contribute to the assessment of the hypothalamic-pituitary-gonadal set-point at least in males. (C) 2004 Elsevier Ireland Ltd. All rights reserved.