Occult hyperprolactinemia in infertile women.

OBJECTIVE

To define the hypersensitive status of PRL secretion in normoprolactinemic infertile women and determine the incidence of occult hyperprolactinemia among them.

DESIGN

The potential for PRL secretion was examined in 463 women.

SETTING

Outpatient clinic in a university hospital.

PATIENTS

Three hundred sixty-seven infertile women and 96 healthy volunteers.

INTERVENTIONS

Patients were treated with bromocriptine, 2.5 or 5 mg/d for 3 months.

MAIN OUTCOME MEASURES

Prolactin response to thyrotropin-releasing hormone (TRH), circadian rhythm, and serum PRL changes during the menstrual cycle.

RESULTS

Approximately 15% of infertile women showed an exaggerated response to TRH, and 95% among them had clinical disorders such as galactorrhea, luteal insufficiency, and menstrual disturbances. Bromocriptine proved effective in 90% of these women. Transient hyperprolactinemia was observed at night in 80% of normal PRL responders who had galactorrhea. Bromocriptine was effective in 75% of these women. Transient hyperprolactinemia during the menstrual cycle was observed in 43% of normal PRL responders with luteal insufficiency, 85% of whom responded to treatment with bromocriptine.

CONCLUSION

In infertile women, the TRH test helps in the selection of patients who may respond to bromocriptine. Among normal PRL responders, 60% of patients with galactorrhea and 47% of those with luteal insufficiency recovered after bromocriptine treatment. From these results, patients who exhibit clinical abnormalities such as galactorrhea and luteal insufficiency should undergo extensive PRL testing.