Canadian women are waiting longer than ever before to have kids and that means more risks for new moms and newborns alike.

Statistics Canada says women between the ages of 35 and 39 had 52.3 babies per 1,000 women while those aged 20-24 were having 45.7 kids per 1,000 women in 2011.

Those numbers are up for women 35-39 and down for those 20-24, signifying a widening gap since 2010.

Waiting longer can lead to more difficult labour for women, an increase in chromosome abnormalities, such as Down syndrome in kids and an increased strain on the medical system overall, doctors say.

Gynecologist Dr. Jenna Rawlins, who practises in Windsor, Ont., said older pregnant women need more care before and during child birth. They require, on average, more ultrasounds, are admitted while pregnant more often than younger women, and are more likely to be induced or need a caesarean section, she said.

"So it’s definitely more resources, but not necessarily during the labour process itself," Rawlins said. "Younger moms have easier pregnancies in terms of their own health. And, they have easier labours."

Older women also have an increased risk of blood pressure problems and diabetes while pregnant, Rawlins said.

'Definitely a trend'

Still, she said older pregnancies are "definitely a trend."

"I see it a lot in professional and university-educated women," Rawlins said. "It’s probably because women in their 20s are still in school — college or university — or trying to establish themselves in their careers."

That was the case for 34-year-old Natasha Thiessen, a regional vice president for a virtual tourism company in the real estate industry, who has three-year-old twin boys and just gave birth to a daughter this week in Windsor, Ont.

"I think you’re more into yourself in your 20s," she said. "I got married a little later in life. I focused on career in my 20s and I had a lot of fun doing that. I moved and travelled for work. I decided to enjoy my marriage a little first."

Thiessen said she never once considered the risks.

"I feel the medical field has moved on in really positive ways and that I'd be safe," she said.

Even Rawlins waited until she was 36 before she had a baby — after 12 years of schooling.

"All your focus at that point is learning. I had to establish my practice and be confident in my office being up and running," Rawlins said. "And it had to be right for my husband as well."

More prepared

Rawlins said that women who wait, though, seem more prepared for a family life.

"Women in their mid- to late-30s are proactive in their research, have done reading and have everything planned to a tee," Rawlins said.

Thiessen said she was one of those women.

"Anything I could plan, I did. If I could find out the sex of the baby, I wanted to. If I could find out the due date, I wanted to. I had planned C-sections. The nursery was planned."

"I'm as ready as I'm ever going to be."

Rawlins does warn women not to wait too long, though.

"After age 40, fertility rates sharply decrease. Do not wait until after age 40," she said. "I think some women have an unrealistic expectation of how easy it is to become pregnant."