Plasma prolactin concentrations and pregnancy-induced hypertension.

Human prolactin (PRL) has been related to various pathologic disorders known to be associated with osmoregulation and hypertension. In this study, we compared changes in plasma PRL concentrations in normal pregnant patients to those in patients with severe pregnancy-induced hypertension (PIH). Comparison of plasma PRL concentrations collected antepartum, at delivery, and 48 hours postpartum failed to distinguish women with PIH from those without. Only women with PIH, however, showed a significant rise in systemic PRL concentrations between admission to the study and delivery. Antepartum abnormalities in plasma PRL concentrations associated with PIH may not have been detected because of diurnal variations in PRL secretion.