Having a baby after 35: What to know

More American women are waiting until later in life to start their families, according to a recent Centers for Disease Control and Prevention (CDC) study, and the trend continues to grow. In fact, 21% of all births in the U.S. in 2023 were to women age 35 and older, up from just 9% in 1990.

While the numbers may surprise some, experts say the shift reflects changing social norms, expanded career opportunities, and a growing emphasis on education and personal goals before parenthood.

“There are lots of reasons women are waiting,” says Dr. Joanna Adamczak, a maternal fetal medicine doctor and chief medical officer at Sharp Mary Birch Hospital for Women & Newborns. “It’s multifactorial. Women are getting an education, building careers, getting married later — and therefore, starting families later. Year after year, we continue to see the average age of childbirth increase.”

Is 35 the magic number?

While the age of 35 is often described as a key milestone in pregnancy, Dr. Adamczak says there’s nothing magical about it.

“There’s really not anything special about age 35 itself,” she says. “It’s simply the time when egg quality starts to decrease. After age 35, the chances of having a child with chromosomal abnormalities increase, which is why we use that number as a general threshold.”

Still, that doesn’t mean all pregnancies after 35 are high-risk. But it does mean certain risks rise over time.

Understanding the risks

Dr. Adamczak explains that pregnancy risks are typically grouped into two categories: risks for the baby and risks for the mother.

“For babies, we see increased chances of chromosomal abnormalities, low birth weight and preterm delivery,” she says. “For mothers, there are higher rates of conditions like gestational hypertension, gestational diabetes, preeclampsia and a greater likelihood of needing a cesarean delivery.”

However, she emphasizes that increased risk does not mean inevitable complications. “Those risks are higher, but they’re not exponentially higher,” Dr. Adamczak says. “Not every woman over 35 will have a complicated pregnancy.”

The role of IVF in pregnancy over 35

Because fertility declines with age, some women turn to in vitro fertilization (IVF) to conceive. Dr. Adamczak notes that IVF can help many families achieve pregnancy, but it also carries additional considerations.

“As you get older, fertility decreases, so the chance of getting pregnant with each cycle goes down,” she says. “Once a pregnancy is achieved through IVF, complications do increase — including placental complications and preterm delivery — along with the maternal risks we may see in women over 35.”

Why prenatal care matters

One of the most important steps women can take when planning a pregnancy after 35 is optimizing their health beforehand.

Dr. Adamczak recommends that women ensure there aren’t any pre-existing medical conditions. If there are, talking with a health care provider is essential.

“High blood pressure should be well controlled,” she says. “Diabetes should be well controlled. When your health is at its best, it gives you the best chance for a healthy pregnancy.”

Prenatal screening also plays a critical role by providing families with essential information. “It helps guide decision-making and allows families to understand their options as the pregnancy progresses,” Dr. Adamczak says.

Is there an ideal age to have children?

While many may wonder what the ideal age for pregnancy may be, according to Dr. Adamczak, there’s no one-size-fits-all answer.

“I don’t think there’s an ideal age,” she says. “It’s whatever is best for you and your social situation. The ideal time is when you’re at your healthiest.”

She encourages women who are thinking about pregnancy — at any age — to partner with their doctor early.

“Get prenatal care and talk with your physician,” Dr. Adamczak says. “That’s the most important step in giving yourself and your baby the best possible outcome.”

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