Serious birth defects that strike possibly hundreds of babies each year in Quebec could be avoided, according to a new study.

Researchers found that more than six per cent of pregnant Quebecers in the study took prescription drugs that are known to be dangerous for fetuses at some point during their gestation, although that might have been because the pregnancies were unplanned.

'Canada has been riding on this risk-management program which is very weak, going on the good faith of the prescriber and the user'— Prof. Anick Bérard

The research, led by the Université de Montréal, shows that half of the expectant mothers who consumed the potentially dangerous medications opted for abortions — a rate that was substantially higher than for the rest of the population.

Lead author Anick Bérard said Tuesday the congenital malformations could be prevented with better communication between physicians and patients.

Bérard, who believes the statistics are similar for pregnant women across the country, is urging governments to improve monitoring for drugs that pose a risk to embryos.

"Obviously, Canada has been riding on this risk-management program which is very weak, going on the good faith of the prescriber and the user," said Bérard, an epidemiologist from the Université de Montréal's pharmacy department.

"Well, now we know that it does not work."

The study, available online and to be published in an upcoming issue of the British Journal of Obstetrics and Gynaecology, examined data from 109,344 Quebec women, aged 15 to 45, who were pregnant between 1998 and 2002.

Researchers found that 6,871 of the pregnant women filled out at least one prescription for medications that are known to threaten fetuses.

Bérard said the potentially dangerous substances include drugs to treat anxiety, epilepsy and severe acne.

Unplanned pregnancies

As an example, she explained that some of the stronger acne medicines can increase the average three-per-cent risk of congenital malformations tenfold.

"You have a 30 per cent chance of having a baby with a birth defect — which is huge, it's one out of three," Bérard said.

She identified major defects as anything from a hole in a baby's heart to a missing limb.

In the study's sample, the rate of birth malformations in the general population was an unusually high seven per cent. For the women who consumed the prescription drugs, it was more than eight per cent.

With roughly 80,000 births per year in Quebec, one percentage point translates to about 800 birth malformations annually, Bérard said.

"One per cent is a lot of people, a lot of babies," she said.

Bérard believes the majority of the medications involved were taken in the first weeks of unplanned pregnancies, when most women still don't know they're expecting. About half of Quebec pregnancies are unplanned.

The best way to prevent birth defects caused by prescription drugs? Plan your pregnancy, she said, and take oral contraceptives when necessary.

Good communication key

Bérard said one of the major challenges is reaching out to sexually active teenage girls, who often share acne medication without knowing the potential consequences if they get pregnant.

The Canadian Patient Safety Institute, a not-for-profit organization that advocates safer health-care practices, held a week-long campaign this month promoting communication in the health system.

"Good communication is key and it doesn't matter whether it's from the patient's perspective or from the caregiver's perspective," said Paula Beard, the institute's director of operations.

"Just because we're talking about health care doesn't make it any different than any other aspect of our life. Good communication is a transferable skill no matter what."