Stay healthy and baby will be healthy too

While many birth defects are caused by genetic, environmental or unknown factors, a mother-to-be's behaviours also can heighten the risk of birth abnormalities.

Here are suggestions for pregnant women on improving the chances for a healthy birth, courtesy of the Nemours Foundation:

Even before you're pregnant or when you're trying to conceive, take folic acid supplements, and make sure you've had all the necessary vaccinations and that you've tested negative for any sexually transmitted diseases.

Once you are pregnant, talk to your doctor about any prescription or over-the-counter medications you take.

Don't drink any alcohol, take drugs or smoke cigarettes, and stay clear of secondhand smoke.

Take vitamins and have regular prenatal visits with your doctor to be sure your baby is healthy.

Maintain a healthy diet, and get regular exercise as recommended by your doctor.