The ability to produce children without undue difficulty. A man’s fertility depends on the production of normal quantities of healthy sperm in the testes (see testis), which, in turn, depends on adequate production of gonadotrophin hormones by the pituitary gland at the base of the brain. Fertility in males is also dependent on the ability to achieve an erection and to ejaculate semen into the vagina during sexual intercourse. Males become fertile at puberty and usually remain so, but to a lesser degree, well into old age. A woman’s ability to conceive depends on normal ovulation (the monthly production of a healthy ovum by 1 of the ovaries) and the ovum’s unimpeded passage down a fallopian tube towards the uterus; on thinning of the mucus surrounding the mouth of the cervix to enable sperm to penetrate; and on changes in the lining of the uterus which prepare it for the implantation of a fertilized ovum. These processes are in turn dependent on normal production of gonadotrophins by the pituitary gland, and of the sex hormones oestrogen and progesterone by the ovaries. Women become fertile at puberty, and they remain so until the menopause around the age of 40 to 50. (See also fertility drugs; infertility.)
Fertility |
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