What you need to know about getting pregnant after 35

Laura Rucchin didn't expect to have a geriatric pregnancy. In fact, she had it all mapped out: By 25, she’d be blissfully married with at least three kids. But it didn’t exactly work out that way. Rucchin delivered her first and only baby, a healthy seven-pound boy, when she was 42 years old. “I never intended to have a child that late,” she says. But after a series of dating mishaps and a broken engagement, Rucchin chose to focus on her career while waiting for the right partner. “He didn’t come along until I was 38.”

Rucchin is in good company. In Canada, nearly one in five babies are born to women age 35 and older, widely considered “advanced maternal age”—and sometimes referred to by its outdated (and rude!) name, geriatric pregnancy. That rate is expected to continue climbing, according to the Canadian Institute for Health Information.

Most older women have healthy pregnancies, but there are some risks to pregnancy after 35 years of age.

The good news: 35 is simply a starting point for advanced maternal age. Risks don’t increase significantly until you’re over 40, and even then they’re typically greater in women who are pregnant with their first child. “A first pregnancy in an older woman can be harder on the body,” notes Keyna Bracken, a doctor in Hamilton with a special interest in obstetrics and women’s health, “simply because it hasn’t done this before.”

Geriatric pregnancy risks

Miscarriage

Egg quality declines as you age, so there’s a greater chance a positive pregnancy test won’t progress into a healthy pregnancy, says Bracken. While the miscarriage rate among 25-year-olds is about 10 percent, it doubles to about 20 percent by age 35 and then climbs to roughly 50 percent by the mid-40s.

Genetic disorders

“Poor egg quality can also result in more genetic disorders, like Down syndrome and trisomy 18.” she adds. For example, in women under 35, less than 20 in 100,000 babies are born with Down syndrome. By age 40, the prevalence in 120 in 100,000 births.

Ectopic pregnancy

At age 40 Rucchin had an ectopic pregnancy, which is four to eight times more common in women 35 and up, according to the Society of Obstetricians and Gynaecologists of Canada (SOGC). Doctors had to remove the Fallopian tube in which the ectopic pregnancy occurred, which significantly lowered her chances of getting pregnant. After two years and three rounds of in vitro fertilization, she finally conceived again, only to miscarry in the first trimester.

Pregnancy complications

The risk for many complications—including gestational diabetes, increased blood pressure (which can cause preeclampsia), placental problems and multiple births—increases with age, although not everyone is equally at risk.

Caesarian section

Up to half of mothers age 40 and older have a Caesarian section, often due to a medical complication, the baby being breech, or the doctor or midwife inducing labour.

Induction

Induction is more common among older moms in part because of the increased risk of stillbirth late in pregnancy: Researchers at Yale School of Medicine found that women ages 40 to 44 had a similar stillbirth risk at 39 weeks as women ages 25 to 29 did at 42 weeks. As a result, the SOGC suggests women age 40 and up should be considered post-term at 39 weeks. However, if your goal is to have a vaginal birth, Sabina Fella, a registered midwife based in Toronto, recommends discussing birth options with your health-care provider.

Having a healthy pregnancy after 35

Despite the risks, many women have a healthy pregnancy after 35 years of age. Being generally healthy before you conceive and during your pregnancy (regardless of your age) can help—this means eating well, exercising, nixing smoking and drinking, reducing stress and getting adequate rest, says Fella.

Screening for geriatric pregnancy risks and complications

Due to the greater risk of genetic conditions, the SOGC recommends doctors advise women age 35 and up to have standard prenatal screening, done at around 12 weeks, to detect the risk of any chromosomal abnormalities.

A newer blood test called Non-Invasive Prenatal Testing (NIPT) can more accurately detect some conditions. While NIPT costs $500 to $900, it can help pregnant women decide whether to have amniocentesis, a diagnostic test that carries a small risk of miscarriage. (The Ontario government will cover NIPT if you're over age 40).

Because women who are over 40 are at least three times more likely to develop gestational diabetes than younger women, the standard glucose screening test, typically done between 24 and 28 weeks, is especially important. Staying on top of any potential complications means they can be managed as early as possible, says Bracken.

About our experts: Keyna Bracken is an associate professor in the department of Family Medicine at McMaster University and has a full time academic clinical practice at McMaster Family Practice. 

Sabina Fella is a registered midwife based in Toronto,