A Woman’s Age at First Pregnancy: Why It Matters

By Sarah Schindler

There is no question that women today are having children later than their mothers and grandmothers. The National Center for Health Statistics recently reported that in 2014, the average age of the first-time mother was 26.3—up from just 21.4 in 1970. While the shift is partially attributable to a downturn in the rate of teen pregnancies, there has also been a clear uptick at the other end of the spectrum. Across all the first-time pregnancies reported in 2014, only 13.4 percent of women were under 20 years old, while 21.1 percent were aged 30-34, and 9.1 percent were 35 and over.

More and more women are waiting until their 30s and 40s to have babies, but they are not necessarily discussing the realities of age-related risks associated with pregnancy. Egg freezing companies encourage women to take steps to preserve their fertility, but with services costing upwards of $10,000 to 12,000, only a handful of women can give this option more than a passing thought. Many women are generally aware that there are risks associated with waiting longer to have babies, but they may be in the dark about the specific details.

The reality is, a woman’s age can impact her ability to get pregnant, her chances of having a healthy baby, and her chances of developing certain health problems herself.

For starters, The American College of Obstetricians and Gynecologists (ACOG) puts it plainly: a woman’s fertility starts to decrease at age 32 and decreases more rapidly beginning at age 37. This is because a woman is born with a fixed number of eggs, and over time the eggs decrease in number and become harder to fertilize. Women may find it helpful to keep these general milestone ages in mind, so they are prepared to deal with the challenges they may face when they do eventually try to get pregnant.

Women should also be aware of how their age at pregnancy may affect their baby’s health. It is widely accepted that older women have an increased risk of having children with health problems caused by missing, damaged, or extra chromosomes—problems including Down syndrome, Tay-Sachs disease, and cystic fibrosis.

Perhaps least discussed are the potential effects of delayed pregnancy on a woman’s own health. ACOG cautions that as women age, they are at a higher risk for developing high blood pressure and diabetes during pregnancy. Additionally, there could be a connection between a woman’s age at first pregnancy and her risk of developing breast cancer. Studies have shown a correlation between a woman’s exposure to the hormones estrogen and progesterone and her risk of developing breast cancer. Thus, per the Susan G. Komen Foundation, it is not surprising that pregnancy—a time of breast development and hormone changes—affects breast cancer risk. Women tend to lower their overall risk of breast cancer by having their first child before age 35.

Ultimately, women should be empowered to make their own decisions about when to have children, but they should also be informed about the risks.