Why does fertility decline with increasing age
Ans : Ageing of the ovaries is the most prominent factor and is part of the normal ageing changes
that effect all organs and tissues. Most women have about 300,000 eggs in their ovaries at puberty. For each egg that matures and is released [ovulated] during the menstrual cycle; atleast 500 eggs do not mature and are absorbed by the body. By the time the woman reaches menopause which usually occurs between 50-55 years, there are only several thousands eggs remaining. As the women ages, the remaining eggs in her ovaries. Also age, making them less capable of fertilization and their embryos less capable of implantation.
- Fertilization is associated with a higher risk of genetic abnormalities eg. Chromosomal abnormalities such as down syndrome with increasing age. The risk of a chromosomal abnormality in a woman age 20 years in 1/500 while the risk in woman age 45 is 1/20.
- Gynecological problems such as Pelvic infections, tubal damage endometriosis fibroids, ovulation problems etc tends also to increase with age. As the woman gets older, she has more time to develop these conditions, which will adversely affect her fertility.
- Sexual function is also decreased with ageing eg. Libido frequency of intercourse etc.
- The effect of ageing in endometrial receptivity [ability of the endometrium to receive the embryo] is controversial. There is increasing evidence that the receptivity decreases with age.
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