The theory of male contraception is based on suppression of hypothalamic GnRH or decreased pituitary secretion of FSH and LH. Spermatogenesis requires androgen at the initiation phase ands FSH at the terminal phase of spermatid development. FSH and LH levels in the range of 5-20 IU/L are required for normal spermatogenesis. Thus, partial FSH or LH inhibition can reduce or halt sperm production. Christiansen & Lund3 studied the effect of AEDs on sperm in 98 men with epilepsy. When semen samples were requested, only 47 men were able to provide a sample, indicating diminished sexual function in half of these unselected patients. Of the samples received, 50% had low semen volume, 57% had low sperm counts, 89% had abnormal morphology, 9^% had low motility, and 96% showed impaired fertility. These data suggest a direct effect of AEDs on sperm. Further evidence was provided in studies with men taking carbamazepine or phenytoin. Swanson et al8 showed that both drugs are present in higher concentration in semen than plasma, whereas valproate semen levels were lower than in plasma. This probably is based on drug solubility.

Authored By: 
Joyce Cramer
Reviewed By: 
Steven C. Schachter MD
Orrin Devinsky MD
Wednesday, September 1, 2004