Aging, reproductive and sexual changes that occur with
The reproductive system, male or female, is intact but immature at birth and remains immature until the onset of PUBERTY around age 12. Researchers do not know what triggers the physiologic events that take place to initiate reproductive and sexual maturity. However, these events result in the development of SECONDARY SEXUAL CHARACTERISTICS, sex drive and interest, and the ability to produce new life. Male FERTILITY extends from puberty to the end of life, though may diminish somewhat in late old age. Female fertility is finite, starting at MENARCHE (the onset of the MENSTRUAL CYCLE) and ending with MENOPAUSE (the conclusion of the menstrual cycle). Only for a few days each month is a woman capable of CONCEPTION.
The hormones of sexual and reproductive maturity have numerous and far-reaching effects in the body. Men and women alike have the spectrum of sex hormones: ESTROGENS and ANDROGENS. Androgens dominate in men; estrogens dominate in women. These hormones account for secondary sexual characteristics and reproductive ability as well as MUSCLE mass and STRENGTH, BONE DENSITY, lipid metabolism, aspects of cardiovascular function, cognitive clarity, BRAIN function, mood, and emotion.
Age-related hormonal changes are most prominent in women, who experience significant transformation in their bodies with menopause. The cessation of OVULATION means a pronounced drop in estrogen within the body, affecting not only reproductive capability but also the functions of nearly every system in the body. Health concerns that arise from these changes include increased risk for OSTEOPOROSIS, CARDIOVASCULAR DISEASE (CVD), and certain types of cancer. Men also experience age-related changes in sexuality and reproductive function. A man’s testosterone level peaks when he is in his early 20s and gradually declines with each decade of life. By age 60 most men have about half the testosterone they had at age 25. This decline results in changes such as diminished muscle mass and strength and male pattern baldness (ALOPECIA). A man’s risk for PROSTATE CANCER significantly increases after age 60. Though a man can still father children even into his 80s, declining testosterone affects LIBIDO (sex drive) and erectile function.
See also ANDROPAUSE; BENIGN PROSTATIC HYPERPLASIA (BPH); ERECTILE DYSFUNCTION; LIFESTYLE AND HEALTH; MENSTRUATION; PROGESTERONE.
