The reported response of sperm count to
clomiphene citrate therapy in subfertile males with idiopathic
oligozoospermia has been widely variable. The author postulates that this may be due in part to patient heterogeneity that may be reflected in pretreatment hormonal status. Seventeen patients with idiopathic
oligozoospermia (mean +/- SE sperm density of 7.3 +/- 1.2 x 10(6) sperm/mL, mean FSH of 5 +/- 0.5 IU/L) were studied. Pretreatment basal LH, FSH,
testosterone, free T4, and
prolactin levels as well as
LHRH-stimulated LH and FSH levels were examined in relation to pretreatment semen parameters and percent change in sperm count after a mean of 7.2 +/- 0.6 months of
clomiphene citrate therapy. The percentage of motile sperm correlated with basal LH (r = .59, p = .02, n = 16) and free T4 levels (r = .62, p = .02, n = 13).
Clomiphene citrate therapy was associated with a significant increase in total sperm count (mean percent change 261 +/- 117, p = .02) and in total motile sperm count (mean percent change 370 +/- 216, p = .03). Percent change in total sperm counts and in total motile sperm counts correlated positively with pretreatment
prolactin levels (r = .64, p = .007, n = 16, and r = .62, p = .01, n = 15), but not with the levels of other
hormones. The results suggest that in patients with idiopathic
oligozoospermia (1)
clomiphene citrate therapy may be more effective in the subgroup of patients who have relatively higher
prolactin levels, (2) basal and stimulated
gonadotropin levels may not be helpful in predicting the response to
clomiphene citrate therapy, and (3) lower sperm motility is associated with relatively higher free T4 and lower LH levels. The underlying mechanisms and the clinical utility of the current observations deserve further study.