The problem with lifestyle risk factors, though, is that the behaviors really should be in place before a woman becomes pregnant, Katz and Correa said. Because birth defects develop so early in pregnancy, to truly protect her child, a woman should be fit, have any diabetes under control and be taking folic acid before conception.
Take, for example, the need to have good folic acid levels. "Neural tube abnormalities occur at the very beginning of the pregnancy, even before the woman is likely to know she's pregnant," Katz said.
Other preventive measures, however, can be undertaken after a woman knows she is pregnant. One important step is to review all prescription and non-prescription medications with an obstetrician, to make sure nothing is being taken that could damage the fetus.
"Whenever she is pregnant and a drug is prescribed to her, she should ask, 'Is this drug safe to take during pregnancy?' If the answer is, 'I don't know,' that needs to be researched further," Katz said.
Expectant mothers also need to be cautious when it comes to exposure to infectious diseases. When traveling during pregnancy, for instance, it's important to be inoculated against prevalent diseases or take steps to avoid exposure.
Katz cited the example of a woman receiving anti-malarial treatment before visiting a part of the world where malaria runs rampant, or receiving a rubella immunization before traveling. But there are infectious diseases that have swept the United States that women should take protective measures against, as well.
"Swine flu is a very important disease to avoid in pregnant women because it can cause the death of the fetus," he said.
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