ABSTRACT
OBJECTIVE: To evaluate the amniotic fluid levels and each ratio of activin A, inhin A and B in Down's syndrome and other complicated pregnancies. METHODS: This study was performed in 71 women who had undergone a midtrimester amniocentesis with the clinical indications and whose pregnancy outcome was retrospectively determined. Ten Down's syndrome, 15 complicated pregnancies including, preeclamsia, gestational diabetesis mellitus, preterm labor, intrauterine growth restriction (IUGR), and 46 noncomplicated pregnancies with normal chromosome were included in this study. Amniotic fluid activin A, inhibin A and B were measured using enzyme linked immunosorbent assays (ELISA). Statistical analysis was performed with Mann-Whitney U test and regression analysis. RESULTS: There were significant positive correlation (r=0.277, p=0.011) between the ratio activin A/ inhibin B level and maternal age and significant positive correlation (r=0.261, p=0.015) between maternal age and the ratio inhibin A/inhibin B level. There were also significant positive correlation (r=0.202, p=0.045) between gestational weeks and inhibin A levels and significant positive correlation (r=0.474, p<0.001) between gestational weeks and inhibin B levels. Amniotic fluid inhibin A and inhibin B levels were significantly (p<0.05) decreased in Down's syndrome compared with the normal chromosomal groups but there was no difference in the ratio activin A/inhibin A and in the ratio activin A/inhibin B between these groups. The amniotic fluid levels of activin A, inhibins (A and B), each ratio of complicated pregnancies groups with normal chromosome was not significantly different from those of uncomplicated pregnancies with normal chromosome. CONCLUSION: This study revealed that amniotic inhibin levels were significantly decreased in Down's syndrome. But, activin A and each ratio were unchanged. The results suggest that activin A may be relatively decreased in each case of Down's syndrome.