The treatments include drug therapy or possibly surgery to improve the situation. There is no effective treatment for lack of sperm. Low sperm count can be treated with artificial insemination or in vitro fertilization with partner or donor sperm. A testicular biopsy is done for men who have no sperm in the ejaculate to find out whether they have immature sperm in the testes. In vitro fertilization, intrauterine insemination, or gamete intrafallopian transfer are done for reproduction in such cases. For retrograde ejaculation (the ejaculation of semen into the bladder rather than out through the penis), sperm may be recovered from the bladder, washed, and used for insemination. Surgery can be done to reverse a vasectomy or to repair enlarged veins in the scrotum (varicocele repair). Surgery also may be done to correct blockages or absence of the vas deferens.