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.
Sexual dysfunction
Whether or not aging directly affects women's sexual functioning during menopause is another area of controversy. However, many studies, including Hayes and Dennerstein's critical review, have demonstrated that aging has a powerful impact on sexual function and dysfunction in women, specifically in the areas of desire, sexual interest, and frequency of orgasm. In addition, Dennerstien and colleagues found that the primary predictor of sexual response throughout menopause is prior sexual functioning. This means that it is important to understand how the physiological changes in men and women can affect their sexual desire. Despite the seemingly negative impact that menopause can have on sexuality and sexual functioning, sexual confidence and well-being can improve with age and menopausal status. Furthermore, the impact that a relationship status can have on quality of life is often underestimated.