How does age affect fertility?

Fertility in women starts to decrease at age 32 years and becomes more rapid after age 37 years. Women become less fertile as they age because they begin life with a fixed number of eggs in their ovaries. This number decreases as they grow older. Eggs also are not as easily fertilized in older women as they are in younger women. Problems that can affect fertility, such as endometriosis and uterine fibroids, become more common with increasing age as well.

Older women are more likely to have preexisting health problems than younger women. For example, high blood pressure is a condition that is more common in older women.

If you are older than 35 years, you also are more likely to develop high blood pressure and related disorders for the first time during pregnancy. The risk of developing diabetes or gestational diabetes increases with age as well.

High blood pressure poses risks that include problems with the placenta and the growth of the fetus.

If you have diabetes, you are at greater risk of having a child with birth defects. The risks of high blood pressure, miscarriage, and macrosomia, a condition in which the fetus grows too large, are increased as well.

The overall risk of having a child with a birth defect is small. However, the risk of having a child with a birth defect caused by missing, damaged, or extra chromosomes is increased in older women.

Testing can be done during pregnancy to screen for or detect certain birth defects in the fetus.

Screening tests assess the risk that a baby will be born with certain disorders. All pregnant women should be offered screening tests for birth defects. Diagnostic tests show whether the baby actually has a certain disorder. Diagnostic tests are available for some, but not all, inherited defects and many chromosomal disorders. They include a targeted ultrasound exam, amniocentesis, and chorionic villus sampling.

Older women have a higher risk of multiple pregnancies than younger women. In addition, some fertility treatments carry an increased risk of multiple pregnancies.

Multiple pregnancies can cause serious problems, including preterm birth, preeclampsia, fetal growth problems, and gestational diabetes. The risk and severity of these problems increase with the number of babies.

Older women are at increased risk of preterm labor and Stillbirth. Babies born preterm can have serious short-term and long-term health problems. The risk of stillbirth also is greater in women who are older than 35 years.

Women who are in their 30s are more likely to need a cesarean delivery than women who are in their 20s. Like any major surgery, cesarean delivery involves risks. Risks include infection, injury to organs such as the bowel or bladder, and reactions to the anesthesia used. These problems occur in a small number of women and usually are easily treated.

Before pregnancy, things you can do to increase your chances of having a healthy baby:

1. See your health care provider for a preconception care checkup.
2. Eat a healthy diet.
3. Take 400 micrograms (0.4 mg) of folic acid daily for at least 1 month before pregnancy and during pregnancy to help reduce the risk of having a baby with a neural tube defect.
4. Exercise regularly.
5. Lose weight if you are overweight or obese.
6. Stop smoking, drinking alcohol, and taking illegal drugs.
7. Avoid contact with substances in your home or workplace that could be harmful during pregnancy.

During pregnancy, things you can do to increase your chances of having a healthy baby:

Continue to take good care of yourself during pregnancy, and get early and regular prenatal care. At each prenatal care visit, your health care provider will monitor your health and your baby’s health and manage any problems should they arise.

By Dr. Samer Cheaib

Specialist OB/GYN