Cancer and its treatments can sometimes have a profound affect on libido and sexual function which in males is most often erectile dysfunction and women vaginal dryness or soreness.

In males, trauma to the pelvic region or spinal cord can damage veins and nerves needed for an erection. Surgery of the colon, prostate, bladder, or rectum may also damage these nerves. Radiotherapy to a lesser extent can also have an adverse affect but this depends on the dose and technique of administration. Drugs given for prostate cancer can reduce the male hormone (testosterone) levels, the most common culprit being LHRH modifiers (eg zoladex) but other drugs for depression and high blood pressure can also compromise sexual function.

In women, radiotherapy to the lower pelvis can damage the glands which moisten the vagina and cause some thickening of the tissues. Drugs such as tamoxifen can cause uncomfortable vaginal discharge and other drugs for breast cancer such as the those known as the aromatase inhibitors (arimidex, aromasin, femara) can cause vaginal dryness. Menopause may reduce the libido in some women. Hot flushes can reduce the sleep pattern impairing libido.

For both males and females psychological wellbeing is very important for a healthy sexual function. Depression, lack out esteem, guilt and anxiety all contribute to loss of libido and erectile dysfunction. If a man experiences loss of erection, he may worry that it will happen again. This can produce anxiety associated with performance and may lead to chronic problems during sex. If the cycle is inescapable, it can result in impotence. Treatment related fatigue and poor sleep patterns can impair libido. Other medical conditions can effect libido even something straight forward such as constipation can affect libido.

Regular exercise will generally improve the state of the blood vessels and increase the flow of oxygen to all tissues including the pelvis, it will also help to loose weight which also helps ED (see how to exercise after cancer).

Pelvic floor exercises are particularly useful as this directly stimulates the muscles around the penis but this need to be performed regularly (see pelvic floor exercises). Diet of course not only will reduce weight, if that is an issue but certain foods have specific benefits on sexual function. Psychological factors in impotence are often secondary to physical causes, and they magnify their significance. The advice to generally improve psychological wellbeing, described above, certainly applies to sexual function