DYNAMICS OF PROLACTIN IN AMNIOTIC-FLUID AND EXTRAEMBRYONIC CELOMIC FLUID IN EARLY HUMAN-PREGNANCY

Concentrations of prolactin were measured by an immunoradiometric assay in 26 matched samples of amniotic fluid, extraembryonic coelomic fluid and maternal serum from 9 to 12 weeks of pregnancy and in a further 131 amniotic fluid samples from 9 to 20 weeks. Low levels of prolactin (median 40 MU/l) were present in amniotic fluid from 9 to 12 weeks. Levels in the coelomic fluid were higher (median level 371 MU/l; P < 0.0001) than in amniotic fluid. From 13 weeks, there was a rapid rise in amniotic fluid prolactin to reach a peak at 19 weeks (median level 99850 MU/l). The pattern of increase of prolactin in amniotic fluid is similar to. but occurs 2 weeks later than that for insulin-like growth factor-binding protein-1, another major decidual product.