Changes in prolactin levels with the menopause: The effects of estrogen/androgen and calcitonin treatment

Abstract

Prolactin levels were evaluated over a 2-year period in three groups of postmenopausal women: group A consisted of 35 untreated women distributed according to time since the menopause; group B consisted of 17 women on a combined estrogen/androgen preparation (Gynodian depot®) intramuscularly at monthly intervals; and group C consisted of 12 women on 100 units of salmon calcitonin intranasally on alternate days and 1500 mg calcium daily. The control group (group D) consisted of 11 healthy premenopausal women. Serum prolactin, estradiol, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured at the onset and 6-month intervals over 24 months. Mean serum prolactin concentrations decreased significantly during the second postmenopausal year in untreated women (p = 0.0001 and p = 0.0000 after 18 and 24 months, respectively) when compared to either the levels in premenopausal women or those at the beginning of the menopause (p = 0.0007). Neither combined estrogen/androgen nor calcitonin therapy significantly influenced prolactin levels which were similar throughout the observed period. In the group on a combined estrogen/androgen preparation, physiological estradiol concentration together with a suppression of gonadotropins during the first 6 months of therapy were achieved. In women treated with intranasal salmon calcitonin, estradiol, FSH and LH levels were unchanged. Our results show that prolactin levels decrease significantly during the second year of the menopause. Neither combined estrogen/androgen, nor salmon calcitonin therapy had any effect on serum prolactin concentrations in post menopausal women.