Physiology and Sexuality in Aging

1. Physiology and Sexuality in Aging Gerontology 410 Jan 2008

2. Introduction • Physiological changes in the human are gradual and the body acomodates them. The potential for sexual expression lasts well into the eighties and nineties and we are not clear how the physiological changes occur at these ages. • We must look back to the middle years to see where these changes begin. First, body appearance begins to change. Breasts may sag, the abdomen become more creased, fatty tissues around the vulva become displaced.

3. Physiological change • The ovaries and the uterus begin to shrink. The vaginal walls become thinner and less elastic. This loss of elasticity occurs throughout the whole body and it is noticed over the whole of the climateric change. It can start with the cessation of menses and the loss of fertility and then extend into old age. As menopause proceeds there is a gradual loss of estrogen and progesterone. This results in the decrease in the synthesis of proteins, a decrease in fatty tissue synthesis in the genital tissues.

4. Physiological change • What does not decrease is the sense of libido, however more time is needed for stimulation and lubrication. This change in the responsivity time is often co-related to the time it now takes the man to reach and sustain and erection. With the loss of estrogen there is drying of mucus membranes throughout the body and therefore there is less lubrication in the vaginal linings. • Examining the four stages of the sexual act we observe the following

5. Physiological change • In the excitement phase-Masters and Johnson described this as follows: increases in heart rate, breathing rate, nipples become erect, sexual flush, muscle tone changes, contractions occur in the anal sphincter, clitoris swells, vaginal walls become lubricated, uterus elevates, penis become erect, testicles are drawn up into the body, the labia flatten and become thinner and increase in size, and the vagina stretches.

6. Physiology of sex • Plateau Phase: Continued increase in heart rate and muscle tension. The urinary bladder closes and muscles at the base of the penis begin rythmic contractions. There is some secretion of seminal fluid and the testicles continue to withdraw into the body. The areola and the labia increase in size and the clitoris withdraws. The Bartholin glands produce further lubrication and an orgasmic platform develops as the vagina opening decreases in size. There may be vocalizations occurring at this time.

7. Physiology of Sex • Orgasmic phase: A release of sexual tension, male and female cycles of muscle contraction in the anus and in the women in her lower pelvic muscles, uterine and vaginal contractions. Males ejaculate 2-5ml of semen. There are other involuntary actions and euphoric sensations. There is a perceived tiredness due to endorphin release and a general feeling of relaxation and drowsiness.

8. Physiology of Sex Resolution Phase: Muscles relax and BP drops. There is a refractory period and the penis returns to a flaccid state. Females who are multi-orgasmic may not immediately go to a resolution stage and will become further stimulated. The cervix opens and there is a blood flow reduction to the genitals and nipples. For some women, stimulation at this stage may in fact be painful.

9. Physiology • For the aging male and female subtle changes are recorded. Sex flush decreases and is of shorter duration. In the plateau phase an extension of the excitement period may be longer. There may be reduced contractions in orgasm, which may be sporadic rather than regular. Resolution is faster. Men do not have menopause but their physiology also changes. They have viable sperm but less in quantity, muscles sag, the testes are more flaccid, the prostate may increase in size, the penis stays essentially the same

10. Physiology • Older males take longer to achieve erection, but erection can be maintained longer. The decrease in ejaculatory inevitability is a plus of aging. Some of the phases in the older male may run together or lose some of their clear descriptive boundaries. At orgasm the amount of ejaculate is less and the resolution phase happens more quickly. • Many older males voluntarily withdraw from sexual behavior for no apparent reason from a physiological standpoint

11. Physiology • There are of course many physical illnesses that impact the physiology of the aging person. Cardiovascular disease, respiratory disease, diabetes, hemotological disease can affect sexual desire and function. Many prescribed medications have a direct effect on capacity and interest in sexual expression. Mood elevators, hypnotics, anxiolytics and a wide range of psychotropics have a direct impact on libido and function. • Sex education is essential for a continued satisfactory sex-life into old age.