Effect of transitory hyperprolactinemia on in vitro fertilization of humanoocytes

OBJECTIVE: To examine the changes in plasma prolactin (PRL) during ovarian hyperstimulation (OH) and the influence of hyperprolactinemia on folliculog enesis, oocyte retrieval and in vitro fertilization (IVF) success rates and the usefulness of the metoclopramide (MCP) test in predicting the onset of hyperprolactinemia. STUDY DESIGN: Forty nine cycles of OH were induced in 32 infertile women us ing follicle-stimulating hormone, human menopausal gonadotropin and human c horionic gonadotropin (GI) (n = 36), also in association with gonadotropin- releasing hormone (GII) (n = 13). The MCP test (10 mg, intravenously) was p erformed on fer tile control women (control group, n = 9) and in GI (n = 21 ) and GII (n = 8) patients. RESULTS: Plasma PRL and estradiol levels increased during OH, reaching maxi mum levels on the day preceding oocyte retrieval in GI and GII. Since these two groups exhibited similar PRL curves, they were evaluated ns a single g roup. Patients showing an increase in PRL of > 200% presented a greater num ber of follicles with a mean diameter greater than or equal to 12 mm and mo ve mature oocytes and better IVF success rates than patients with a PRL inc rease less than or equal to 200%. Oocyte retrieval did not differ between f ile groups. Tire MCP test showed hyperresponsiveness in the three groups st udied but, no correlation was found between the PRL increase in this test a nd that during OH. CONCLUSION: Plasma PRL and estradiol levels increase during OH, while the M CP test cannot predict the onset of hyperprolactinemia. Transitory hyperpro lactinemia seems to be associated with an increase in the numbers of follic les with a mean diameter greater than or equal to 12 min and with more matu re oocytes and better IVF success rates.