Age and Fertility

Having a healthy pregnancy, and a healthy baby, becomes increasingly difficult with age. Why? A woman is born with all of the eggs she�ll ever have. After puberty, she begins to ovulate and releases one of these eggs every month. As she ages, therefore, her supply of eggs dwindles.� This reduces her chances of being able to conceive. As a result, the likelihood of a woman getting pregnant in any particular month, under optimal circumstances, is about 25 percent for a woman in her 20s, 15 percent for women in their early 30s, 10 percent in the mid-30s and just five percent for women over 40. Another difficulty with pregnancy later in life is that the number of genetically normal eggs that a woman has decreases with time. This leads to a higher rate of miscarriage and a greater chance for genetic abnormalities in babies of older women. In fact, the odds of a woman in her 20s having a child with Down syndrome are about one in 1,200. In contrast, among children born to women over 40, one child in 38 has a genetic abnormality. While this can be difficult for women trying to conceive after the age of 30, other fertility options, like using donor eggs, are quite successful in later life.