Am I Too Old To Have A Baby?

Many women ask this question as they move into their late thirties. Some have never had children. Others have children, but would like one more. Biologically, we know that the early to mid-20’s are the optimal time for childbearing, but this frequently is not an ideal time for parenthood from a social or educational or economic perspective. Marriages occur later in today’s society; many women who want children are still in school, unmarried and beginning their careers at age 25. So by necessity, many women present to their ob/gyn around age 35, questioning the safety of a pregnancy. Let’s look at some of the realistic risks.

The first question most women ask is “What’s the chance my baby will be normal?” We clearly know that the risk of chromosomal abnormalities (Down’s syndrome, Turners’ syndrome, even molar pregnancies) and nonchromosomal abnormalities (congenital heart defects, for instance) increases with advancing age. At age 25, the risk of having a baby with Down’s syndrome is 1/1250; the risk of having a baby with any chromosome abnormality is 1/476. By age 35, this risk has increased to 1/385 for a Down’s syndrome baby and 1/204 for any chromosome problem. Women who are 35 or older have a 1% higher risk for nonchromosomal birth defects, versus those women under 25. By age 40, the risk is 2.5% above the 25 year old’s risk. So the vast majority of babies born, even to women over 40, are normal, but the risks are increased versus younger women.

For all pregnant women, maternal serum screening (the “triple screen”) is available to help further quantify the true risk of abnormalities in a singleton pregnancy. Maternal serum screening is not accurate for twins and higher order pregnancies. Ultrasound is also very helpful in screening for birth defects, particularly when it is done by specialized technicians in a perinatal referral center. Genetic counseling with a specialist is typically offered to women over 35 or those at other risk for birth defects; amniocentesis or chorionic villus sampling are prenatal diagnostic techniques that can detect many birth defects at or before four months pregnancy.

Medical risks for the mother, which can impact both her and her baby, are also increased in older pregnant women. Hypertension and gestational diabetes are more common; these can effect the baby’s growth and the mother’s health. They are important to screen for early in pregnancy, with continued surveillance until the birth and postpartum period. Older women who have preexisting diabetes, heart disease, hypertension or obesity are especially cautioned to see their ob/gyn before they get pregnant.

In conclusion, the risks of childbearing, both for the mother and her baby, are increased with age. But with careful surveillance and prenatal care, these risks can be minimized. Age-related risks of birth defects can be screened for. Maximizing maternal good health preconceptually (achieving normal weight, stopping smoking, a reasonable aerobic exercise program), along with continuing these good habits throughout pregnancy, will help achieve the best result for the older mother and her baby.

By Scott Williams, MD, FACOG of SSM St. Charles Clinic Medical Group, O’Fallon, MO.