The effects of pregnancy on patients with hyperprolactinemia

Seventy women with amenorrhea with or without galactorrhea associated with high serum prolactin levels and radiologic evidence of pituitary tumors were treated with transsphenoidal tumor resection. The prolactin level was measured in 29 patients before pregnancy, at 3 months post partum or cessation of lactation, and at 6-month intervals thereafter. The results were compared to those of 18 patients who had hyperprolactinemia but no demonstrable radiologic evidence of a pituitary tumor and who responded to bromocriptine and conceived. Our investigations showed that operation resulted in normalization of serum prolactin levels in 74% of patients. Forty of the 49 patients less than 36 years old conceived (80%). Five of 29 patients who were studied before and after operation as well as after delivery showed an increase in serum prolactin levels post partum and persistent amenorrhea suggesting recurrence. Six of the 18 patients who became pregnant after bromocriptine also showed a significant rise in serum prolactin levels above the treatment level. None of the patients in the two groups developed visual changes or symptoms or radiologic changes during pregnancy. These results showed that transsphenoidal operation has a high incidence of success, but some patients may show a rise of serum prolactin levels and persistent amenorrhea after pregnancy or passage of time, suggesting recurrence. Some patients who become pregnant after bromocriptine therapy may have further rises in prolactin greater than pretreatment levels. Follow-up of these patients is indicated.