When are you too old to have a baby?

If we’re to use the glam lives of celebrity moms as examples,it’s easy-peasy to have a kid after age 35. Hallie Barry did it; ditto Madonna, Courtney Cox and Nicole Kidman. While plenty of older women do have healthy pregnancies, a new study suggests that pregnancy risks begin to increase at 35 and increase significantly in women over 40.

Researchers from the Canadian Institute of Health (CIHI) looked at one million hospital births across Canada and found that first-time mothers over the age of 40 are most at risk - one in eight moms over 40 developed gestational diabetes compared with one in 24 women aged 20 to 34.

[Also see: When should you have another baby?]

Unfortunately, the study also found that there's a greater risk to the babies of older moms.Results showed that one out of every 127 babies born to a mom over the age of 40 had chromosomal disorders such as Down Syndrome, compared to one in 1,000 babies born to women aged 20 to 34.

This is sure to come as deeply unsettling news to many Canadian women who are waiting longer to have their first babies. “In Canada,almost one in every five births is to a mother over the age of 35, and this proportion is projected to continue to increase,” says Kathleen Morris, Director of Health System Analysis and Emerging Issues at CIHI in a press release.

It’s no surprise that more women want to have children later in life when their careers are established and financial situations more stable. And for many, waiting is a very good thing – a global study published in March 2011 suggests parents 40 and older are the happiest.

Advances in fertility treatments are making it easier for women to become pregnant later in life (remember Maria del Carmen Bousada of Spain who became pregnant with twins at age 66 and died from cancer at age 69?). But the debate about whether or not older women should become pregnant rages on. Can a woman be too old to become a mom, or do the benefits of waiting to have children far outweigh the risks?

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