Apr 18, 2024 - Health

Pregnancy at 35 has its benefits for mothers in Illinois

Share of Illinois babies born to mothers in select age&nbspgroups
Data: CDC Wonder; Chart: Erin Davis/Axios Visuals

More than half of Illinois babies born last year had birth mothers in their 30s and older, according to provisional CDC data.

Why it matters: In the last few years, age 35 has gone from the start of "geriatric pregnancy," to potentially a maternal-age sweet spot.

By the numbers: 30 is the average age of a woman giving birth in Illinois, per 2023 data.

  • That's the national average β€” and slightly younger than states with the highest maternal ages such as Connecticut, Massachusetts and New Jersey, with averages above 31.

Regions with higher income and education levels "are correlated with increased advanced maternal age," partly because women there are deliberately delaying pregnancy for economic reasons, says Jane van Dis, OB-GYN and assistant professor at the University of Rochester.

  • Roughly 37% of Illinois residents have a bachelor's degree or higher, and the state's median household income hovers around $78,400, per census data. That's compared with 34% and $75,149 nationwide.

The intrigue: 35-year-olds received more prenatal monitoring and had a small decrease in prenatal mortality compared with even those a few months younger, according to a 2021 JAMA Health Forum study.

Catch up quick: 35 became the start of "advanced maternal age" decades ago, thanks to studies on the then-new invasive genetic test called amniocentesis.

  • Researchers determined that for a pregnant person 35+, the chances of carrying a baby with a genetic condition were greater than the risk of pregnancy loss as a result of getting an amniocentesis to test for that condition, Tiffany Pham, OB-GYN and Flo Health medical adviser, tells Axios.

But that's a "dated paradigm" and "there's nothing really particularly magic" about age 35, says Alison Cahill, professor and associate dean of translation research at the University of Texas at Austin's Dell Medical School.

  • We have since learned that the amniocentesis risk is much lower than once was thought.
  • And there are now less-invasive and lower-risk procedures for prenatal genetic screening.

Reality check: Risks, including possible miscarriage, increase much more after age 40, compared with 35.

  • New ACOG guidelines emphasize that pregnancy risks should be considered among patients in five-year age groups β€” ages 35-39, 40-44, etc. β€” instead of a big advanced maternal age group.

Yes, but: Women considering having kids by their mid-30s should be acquainted with their own physiology and possible fertility challenges "much earlier than 35," van Dis says.

The big picture: Insensitive wording has long added to the stigma around later-in-life pregnancy β€” but there's been some progress when it comes to maternal health terminology.

  • In a poll of its users last month, the app Peanut found that 40% of women in their mid-30s or older reported a positive shift in language from their health care providers, moving away from terms like "geriatric pregnancy" to their recommended "35+ pregnancy."

Get more local stories in your inbox with Axios Chicago.


Support local journalism by becoming a member.

Learn more

More Chicago stories

No stories could be found


Get a free daily digest of the most important news in your backyard with Axios Chicago.


Support local journalism by becoming a member.

Learn more