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Throughout history, men and women have wanted to control their fertility. Until the 20th century, however, the only possible methods were abstinence, abstinence during the most fertile days of the menstrual cycle (the rhythm method), or interruption of intercourse before ejaculation (withdrawal, or coitus interruptus). Things improved when barrier methods became available - the condom for men and the diaphragm for women - and they rapidly became the most widely used methods of birth control. The 1960s brought a significant change when birth control pills came into use. Since then, most new methods of birth control have focused on the female reproductive system; in the past three decades, doctors have developed safer and more effective birth control pills, implants, injections, intrauterine contraceptive devices, spermicidal jellies, female condoms, and improved tubal ligation techniques - all for women. In contrast, the only addition to a man's contraceptive options has been the vasectomy. It's an old operation with new refinements, and it's been the choice of more than 45 million men worldwide.
The Male Reproductive System
Procreation often seems like a no-brainer, but, in fact, the entire complex process in both sexes begins with hormones emanating from the brain. The first step is initiated by the hypothalamus, which produces gonadotropin-releasing hormone (GnRH). GnRH then stimulates the nearby pituitary gland to secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Although these hormones were named for their effects on the ovary, they are just as important for male reproductive functions as they are for ovulation.
LH and FSH are released in the brain, then travel through the blood to the testicles, where LH drives the Leydig cells to produce the major male hormone, testosterone. Acting together, testosterone and FSH stimulate the germ cells to produce sperm.
Sperm take about 74 days to mature; then they enter the many tiny seminiferous tubules that carry them slowly through small ducts into the epididymis, a tightly coiled tube about 20 feet in length. Sperm spend about two weeks traveling through the epididymis; it's time well spent, as they …