Sex differences in human physiology
Female fertility declines after age 30 and ends with the menopause. Female physical experiences vary depending on external forces such as diet, marriage patterns, culture, and other aspects. In Western nations menstruation begins to affect females at 13 and menopause starts around 51. In non-industrialized countries, on the other hand, most females begin menstruation at a later age. More lactation in the lifetime of non-western females inhibits ovulation and extends the number of fertile years. Pregnancy in the 40s or later has been correlated with increased risk of Down syndrome in the children. Males are capable of fathering children into old age. Paternal age effects in the children include multiple sclerosis, autism, breast cancer and schizophrenia, as well as reduced intelligence. Adriana Iliescu was reported as the world's oldest woman to give birth, at age 66. Her record stood until Maria del Carmen Bousada de Lara gave birth to twin sons at Sant Pau Hospital in Barcelona, Spain on December 29, 2006, at the age of 67. In both cases IVF was used. The oldest known father was former Australian miner Les Colley, who fathered a child at age 93.
Hormone replacement therapy
Current research that has examined the impact of menopause on women’s self-reported sexual satisfaction indicates that 50.3% of women experience some sexual disturbance in one of five domains, and 33.7% experience disturbances in two of the domains. Of these were desire, orgasm, lubrication, and arousal disturbances. With regards to arousal, they found a significant negative association between age and arousal, in that as women aged they were more likely to report lower arousal scores. In the desire and orgasm domains, 38% of women reported a disturbances in their desire, and 17% reported a disturbance in their orgasm capabilities; of the 17%, 14% were premenopausal, 15.2% were postmenopausal and taking a form of HRT, and 22% were postmenopausal not on a form of HRT. Eight percent of women reported disturbances lubricating during sexual activity; 14.3% in the premenopausal group, 30% in the postmenopausal group not using a HRT, and 11.7% among those postmenopausal women using HRT. Lastly, 21% of women reported pain as a disturbance in their sexual satisfaction — the premenopausal group at 14.3%, the postmenopausal women using HRT at 13.3% and the group with the highest rates, similarly to the other results, was the postmenopausal women not taking HRT at 34%. This study concluded that there was a significant decline in sexual function related to menopause in the pain and lubrication domains.