When Does Fertility Start to Decline?

As more and more women delay starting a family until later in life, they run the risk of decreasing chances of pregnancy. Studies show conclusively that women over the age of 35 suffer more fertility problems than younger women. Does that mean age 35 is the “fertility deadline” for women? Should women reset their biological clocks?

Is 35 too old to have a baby?

The Mayo Clinic reported that a woman’s fertility peaks between age 20 and age 24. The fertility rate remains relatively constant (at about 15–20% below maximum) through age 35. From 40 to 45, though, the decrease is a dramatic 50–95%. This translates as follows: a healthy 30-year-old woman has about a 20% chance per month to get pregnant. By age 40, however, her chance is only about 5% per month.

Even though women today are healthier and taking better care of themselves than ever before, improved health in later life does not offset the natural age-related decline in fertility. A woman is born with all the eggs she will ever have, and as she ages, not only does she have fewer eggs, but the quality of those eggs also decreases.

What are the pregnancy risks after age 35?

By the time a woman reaches her early 40s, the risk of miscarriage increases to the point that more than 50% of pregnancies end in miscarriage. Many happen at such an early stage that they aren’t even noticed (or are passed off as a late period).

Even when pregnancy does occur, older women may have a higher risk of developing gestational diabetes, pre-eclampsia, and placenta previa. There may also be a higher risk of conceiving babies with a low birth weight or with abnormalities such as Down syndrome.

What can an older woman do to ensure a successful pregnancy?

For women over 35 who are set on conceiving, here are a few tips to help minimize the risks:

• Start taking prenatal vitamins
• See your doctor for pre-pregnancy checkups
• Eat well
• Exercise regularly
• Cut out nicotine, alcohol, and drugs

Finally, if you don’t succeed in getting pregnant within six months, see a reproductive endocrinologist (a fertility specialist) to discuss next steps.