Detection of prostate-specific antigen immunoreactivity in amniotic fluid

Objective: To examine whether prostate-specific antigen (PSA) is present in amniotic fluid, whether the amniotic fluid PSA concentration changes with gestational age, and whether there is an association between amniotic fluid PSA and fetal sex. Methods: The PSA concentration was measured in the amni otic fluid of 48 pregnant women. Thirty-four samples were obtained during r outine amniotic fluid analyses performed during gestational weeks 16-18, wh ereas 14 samples were obtained during cesarean section performed after gest ational week 36. Results: PSA was detected in all amniotic fluid samples. T he median amniotic fluid PSA was 0.193 ng/ml during gestational weeks 16-18 and 0.39 ng/ml after gestational week 36 (p = 0.1). Furthermore, no signif icant association was seen between amniotic fluid PSA and fetal sex. The me dian amniotic fluid PSA level was 0.233 ng/ml for the 21 boys and 0.222 ng/ ml for the 27 girls investigated (p = 0.72). Conclusions: These results con firm recent literature reports that PSA may serve as a growth regulator dur ing normal fetal development. However, further studies are necessary to elu cidate the exact role of PSA during fetal development.