Sexual anatomy and responses

Even though sexuality is much more than sexual function or your ability to have sexual intercourse, it may be helpful to be reminded of the sexually sensitive areas of your body and how they respond to stimulation.

Your body

Female sex organs are mostly inside the body. However, outside the body are the outer lips of the vulva, or labia majora (see picture below).

  

  

When parted, these show the thinner, inner lips – the labia minora. These join at the top to cover the clitoris with a hood. The clitoris is usually sensitive to touch. The head of the clitoris, when not aroused, is about the size of a split pea. Just beneath this, towards the vaginal opening, is the urinary outlet or urethra. Further back still is the vagina itself. Beyond the vagina is an area of skin called the perineum and beyond that the anus or opening to the anus. The uterus (womb), the cervix (neck of the womb) and the ovaries lie inside the body.

Other sexual areas on the body include the breasts and nipples, which change in hardness and sensitivity when touched. There are other sensitive areas on the body, such as the nape of the neck, behind the knees, the buttocks and the inner thighs, which respond to direct touch. These areas, which vary from person to person and are known as erogenous zones, may help you achieve intimacy even when sex is not possible or desired.

  

  

Male sex organs are mainly outside the body and include the penis and testes (see picture). The end of the penis is covered by the foreskin, if it has not been removed by circumcision. The ridge on the underside of the head, called the fraenulum, is usually the most sensitive part of a penis. At the very top of the penis is a slit opening to the urethra through which semen and urine are passed.

At the base of the penis there is a bag formed by wrinkly skin called the scrotum. Inside this bag lie the testicles (or balls). These produce sperm, which is then passed through tubes (vas deferens) to mix with other fluids to make semen.

The prostate gland lies deep in the pelvis and surrounds the first part of the urinary tube, the urethra, as it leaves the bladder. The prostate gland produces a fluid that mixes with the sperm to form semen and helps create the intense sensations felt during an orgasm.

The penis, testicles and anus are erogenous zones. The chest and nipples can also be sensitive and the body may have other erogenous zones, which are helpful to understand when sex is not desired or possible.

  

  

Stages of sexual arousal

Sexual desire, also known as libido, is a phrase used to describe a person's interest in sex. It’s generally accepted that people’s desire for sex can vary. For example, desire for sex changes throughout the menstrual cycle and during pregnancy, breastfeeding and menopause.

Excitement or arousal is the phase of sex in which we feel “turned on” and ready for sex. This can be produced by simply seeing someone we find attractive, being touched by or touching, having a sexual fantasy, or having our genital area touched. Arousal may, or may not, lead to orgasm. Orgasm is the sexual climax and a feeling of intense sensation that occurs as areas of the body go into a series of rhythmic contractions.

After sex there is a phase when sexual changes in the body return to normal. As people get older they may lose the ability to become sexually excited repeatedly, but their desire for intimate and sensual touching, hugging and closeness rarely changes.

Body systems that control sexual response

All these sensations and experiences are linked and require certain systems in the body to be working normally. The changes described above will only happen if the body has a good blood supply, if the nerves to the pelvic area are intact, and if the hormone balance is right. However, our desire for sex is greatly affected by our state of mind. If you are depressed, anxious or afraid about your cancer, its treatment or your relationship, you may find it more difficult to be aroused by thoughts of sex. 

You may find it useful to talk to a sexual counsellor if you are having ongoing problems.