A woman's peak reproductive years are between the late teens and late 20s. By
Egg quality starts to decline at age 32 and decreases rapidly after 37. Advanced maternal age also heightens the risk of birth defects. Only 28 percent of women, and 35 percent of men, believe age is the number one contributor to female infertility, the AOA survey found.
They found that, as women age, their egg cells become riddled with DNA damage and die off because their DNA repair systems wear out. Defects in one of the DNA repair genes—BRCA1—have long been linked with breast cancer, and now also appear to cause early menopause.
The decline in egg count and quality is much steeper in a woman's late 30s. That's why the impact of age-related fertility decline is strongest after age 35. Due to a higher percentage of genetically abnormal eggs, other risks increase with age as well, such as the chance of miscarriage or Down syndrome.
At the age of 37, the average woman has around 25,000 eggs left, and by the time she reaches 51, this will have fallen to 1,000. “Just before menopause, your egg supply reaches below 1,000, and ovulations space out before they stop altogether, eventually,” says Dr. Sekhon.
Egg Quality Deteriorates With Age
Your age affects the health of your eggs. Women reach the peak of their fertility at around age 24. After this age, egg quality slowly deteriorates until around age 37, and then deteriorates more rapidly until about age 42.
After age 35, there's a higher risk of pregnancy-related complications that might lead to a C-section delivery. The risk of chromosomal conditions is higher. Babies born to older mothers have a higher risk of certain chromosomal conditions, such as Down syndrome. The risk of pregnancy loss is higher.
After 41 years the egg quality declines rapidly. When the woman is over 37 years old, reduced egg quality is often a contributing factor, when it is difficult to become pregnant. Therefore, it is likely that for some couples infertility is solely due to the quality of the woman's egg.
Geriatric pregnancy is a rarely used term for having a baby when you're 35 or older. Rest assured, most healthy women who get pregnant after age 35 and even into their 40s have healthy babies.
The study published by the University of St. Andrews and Edinburgh University in Scotland found that women have lost 90 percent of their eggs by the time they are 30 years old, and only have about 3 percent remaining by the time they are 40.
Down syndrome occurs in people of all races and economic levels. The risk increases with the mother's age (1 in 1250 for a 25 year old mother to 1 in 1000 at age 31, 1 in 400 at age 35, and about 1 in 100 at age 40). However, 80% of babies with Down syndrome are born to women under age 35 years.
Women lose 90 per cent of the eggs in their ovaries before the age of 30, new research has shown. The mathematical model shows that the average woman has only 12 per cent of her eggs left by the age of 30 and only three per cent by the age of 40.
A woman's peak reproductive years are between the late teens and late 20s. By age 30, fertility (the ability to get pregnant) starts to decline. This decline happens faster once you reach your mid-30s. By 45, fertility has declined so much that getting pregnant naturally is unlikely.
Although female fertility declines with advancing age, it is difficult to predict the overall rate of reproductive decline. The quality of a woman's eggs is highest in her mid 20s through her early 30s, representing the most fertile period in her life.
While it may take a bit longer to get pregnant if you're 35 or older, the average time it takes to conceive is still high. Women under 25 have a 25 percent chance of conceiving per cycle, compared to 15 percent among women between the ages of 35 to 39 (the rate drops to 5 percent by the age of 40).
But the most important factor affecting fertility in women over age 35 is a decrease in egg quality. This decrease in quality impairs fertilization and embryo development, and reduces the chances of achieving a healthy pregnancy.
At 37-38 years, even healthy women will have around 25,000 of their eggs but by then the quality of these eggs also becomes a concern.
Older women are more likely to miscarry or have a stillbirth. They have a greater chance of developing gestational diabetes, preeclampsia, and of delivering a baby who is very small. Then there can be problems with labor, resulting in a higher chance of cesarean birth.
This is because, between the ages of 30 and 40 years, a woman's chance of conceiving per cycle fall from approximately 20% to just 5%.
The stages of adulthood examined here include: Early Adulthood (ages 22--34). Early Middle Age (ages 35--44), Late Middle Age (ages 45--64), and Late Adulthood (ages 65 and older).