Transient hyperprolactinemia in gonadotropin-stimulated cycles for in vitro fertilization and its effect on conception.

The significance of transiently increased serum prolactin (PRL) levels on pregnancy rates in vitro fertilization (IVF) is unknown. The aim of this study was to evaluate PRL levels in IVF patients who conceived and in matched controls who did not. Ten IVF cycles resulting in pregnancy and forty nonpregnant cycles were compared. Prolactin was measured before ovarian stimulation with gonadotropins and estradiol (E2), progesterone (P) and PRL were measured 36 hours, 12 hours, 10 minutes before and 12 hours after human chorionic gonadotropin (hCG) administration at mid-cycle. Serum PRL levels at various time were not significantly higher in the nonpregnant women than in the pregnant women. Twelve hours before hCG, P levels were significantly higher in the nonpregnant women than in the pregnant women (1.5 +/- 0.2 ng/ml [mean +/- standard error] and 0.9 +/- 0.3 ng/ml, respectively; P < 0.05). All women had transient hyperprolactinemia for one to three times during ovarian hyperstimulation. There was no correlation between PRL and E2 in either group. These results do not support the treatment of transient hyperprolactinemia with dopamine agonists in IVF patients.