title: A low sperm concentration does not preclude fertility in men with isolated hypogonadotropic hypogonadism after gonadotropin therapy.
abstract: In order to define the minimal number of sperm needed for conception, we studied semen characteristics of men with isolated hypogonadotropic hypogonadism (IHH) who became sperm-positive during gonadotropin therapy. Twenty-two of 24 men (92%) proved fertile, initiating a total of 40 pregnancies. The mean (+/- standard error of the mean) sperm concentration at the time of conception was 16.7 +/- 4.0 X 10(6)/ml. However, 71% of pregnancies were conceived when the mean sperm concentration was less than 20 X 10(6)/ml; in 16%, the mean sperm concentration was less than 1 X 10(6)/ml. Mean total sperm count correlated highly with sperm concentration (r = 0.67, P less than 0.001). We conclude that men with IHH can initiate conception even when their sperm concentration is well below the conventional lower limit of 20 X 10(6)/ml.
mesh_terms: D000293:Adolescent; D000328:Adult; D006063:Chorionic Gonadotropin / Q000008:administration & dosage; D004359:Drug Therapy, Combination; D005260:Female; D005298:Fertility; D005640:Follicle Stimulating Hormone / Q000097:blood; D006065:Gonadotropins, Pituitary / Q000378:metabolism / Q000627:therapeutic use*; D006801:Humans; D007006:Hypogonadism / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008596:Menotropins / Q000008:administration & dosage; D011247:Pregnancy; D013076:Sperm Count; D013737:Testis / Q000473:pathology; D013739:Testosterone / Q000097:blood
chemical_list: D006063:Chorionic Gonadotropin; D006065:Gonadotropins, Pituitary; D013739:Testosterone; D008596:Menotropins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone