Elevated prolactin levels in oral contraceptive pill-related hypertension.

Twenty women whose blood pressure became elevated during oral contraceptive treatment had higher serum prolactin levels (31 +/- 5.3 microgram/liter) than did 20 normotensive pill takers (16.1 +/- 1.8 microgram/liter) and 20 women who were not taking the pill (14 +/- 1.1 microgram/liter), and the higher level was maintained (30 +/- 3.5 microgram/liter) after the pill was discontinued and blood pressure had become normal. This increase in prolactin levels was not related to differences in age or mode of treatment, and it is thought to reflect an alteration in dopaminergic transmission in patients with pill-related hypertension.