When are women having babies and how old is too old?

Our Commonwealth cousins, Australia and the U.K., are shedding new insight into when couples are having kids.

Reports released by both countries this week confirm people are becoming first-time parents at an older age.

“Over the last 40 years, the percentage of live births to women aged 35 and over has increased considerably,” said Elizabeth McLaren of the U.K.’s Office for National Statistics.

Women over 40 are having babies more often than women under 20 in Britain, for the first time in over seven decades.

The last decade has also seen fewer teen pregnancies in Canada. There were half as many babies born to Canadian teenagers in 2012 than in 1991.

READ MORE: Teen pregnancy rates are falling and experts don’t know why

The average age of a Canadian woman when she gave birth was 30.2 years at last count (2011). Stats Canada noticed then that, in the past five decades, there’s been a decrease in pregnancies for women in their late 20s and an increase for those aged 30 to 34.

That also happens to be the age group having the most babies in the U.K.

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In the land down under, these interesting tidbits came out of the Household, Income and Labour Dynamics in Australia survey.

4 factors that influence when a couple has kids

1. Financial stability

Australian women are the ones deciding when to have a baby.

“A woman’s financial stability and satisfaction with her partner both affect the decision to start a family, while a man’s sentiments on these matters have no impact on the decision,” according to the Sydney Morning Herald‘s analysis.

A man’s income, however, does appear to play a role.

“Each additional $1,000 in weekly earnings increases the probability of pregnancy by 1.4 percentage points.”

2. Marital status

Almost two-thirds of new parents in Australia are married.

In Canada, more couples seem to be switching up the traditional order of things. Britain has also experienced a rise in the percentage of births outside marriage.

3. Co-habitation

The Australian stats found that couples who have kids live together for almost five years on average before having a baby.

They were 8.8 per cent less likely to have a child if they’d been together and childless for more than six years.

You’re also apparently more likely to have a baby after you buy your own home (about 60 per cent of Australian new parents were property owners, despite only 46 per cent of 25- to 35-year-olds owning their own home).

Sky-high housing prices have put that milestone out of reach for many Canadian millennials.

4. Age

Similar to the trend across the pond, one-third of Australian mothers and almost half of fathers are older than 30 when they start having children.

READ MORE: Woman in her 70s gives birth to healthy baby boy following IVF

But how old is too old?

The likelihood of conceiving naturally decreases with age, which leaves some older women turning to fertility treatments.

According to the Canadian Fertility & Andrology Society, there is currently no age cap for a woman who wishes to undergo in-vitro fertilization (IVF). But the group has just started to work on a guideline.

It will examine ethical and legal standpoints, as well as physician opinions, explains executive director Mark Evans of CFAS.

Ontario currently limits provincial funding of IVF to women under the age of 43.

READ MORE: Stop asking couples when they’ll have kids, pleads Ontario man dealing with infertility

Even though there’s the occasional 42-year-old who gets pregnant right away, in general, “women get pregnant easier when they’re younger,” Dr. Al Yuzpe of Vancouver’s Olive Fertility Centre told Global News this past spring.

“And their complications are generally lower when they try to get pregnant in their mid-20s. But that isn’t the norm anymore,” he acknowledged.

Tweet This Click to share quote on Twitter: "And their complications are generally lower when they try to get pregnant in their mid-20s. But that isn't the norm anymore," he acknowledged.

Almost one in five of first-time births in Canada are to women over the age of 35, Yuzpe said. Nearly one in four of all births in Canada are to women over 35.

While putting off childbirth is not always a choice, potential complications associated with it include: needing a C-section, getting gestational diabetes or pregnancy-induced hypertension, and an increased risk of genetic abnormalities. The latter is because “chromosomes become stickier so they don’t divide properly” as women age, Yuzpe explained.

Women who have held off may be comforted to know, though, that their chance of conceiving any given month only drops by five per cent (to 20 per cent) when they hit 30.

“Nobody ever has better than a 25 per cent chance [of conceiving each month], even if they’re 21,” said Yuzpe.

Tweet This Click to share quote on Twitter: "Nobody ever has better than a 25 per cent chance [of conceiving each month], even if they're 21," said Yuzpe.

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