[Prolactin and pregnancy].

The role of prolactin during fetal growth and lung maturation was investigated in humans. Prolactin levels in the maternal, fetal and amniotic compartments were measured by radio-immunoassay in patients with anencephalic fetuses, and patients treated with bromocriptine during pregnancy. Bromocriptine or an active metabolite(s) passed through the term placenta and suppressed prolactin secretion by the fetal pituitary gland. Prolactin levels in amniotic fluid were scarcely affected by bromocriptine treatment. This suggested that prolactin in amniotic fluid was not derived from biosynthesis of the dopamine receptor-mediated process. The maternal and fetal prolactin may not play an obligatory role in the maintenance of pregnancy and fetal growth.