Could traffic pollution be to blame for miscarriages? Some researchers think so.

In a recent Brazilian study of 400 women who had IVF (in vitro fertilization,) scientists found that those who became pregnant in winter, when pollution levels are particularly high, were twice as likely to miscarry in the first eight weeks as those who conceived at other times of the year.

According to University of São Paulo researcher Paulo Marcelo Perin, miscarriage rates were 20 to 30 percent higher in winter months when traffic pollutants are greatest, compared with 10 to 15 percent in other seasons. The Brazilian research team told the American Society for Reproductive Medicine conference in Atlanta, Ga., that these findings may be relevant to other countries where air pollution regularly exceeds levels considered safe by the World Health Organization.

This study comes on the heels of a similar study by American researchers on 7,500 women undergoing IVF that also suggested a decline in fertility due to exposure to nitrogen dioxide, another common air pollutant.  

What do these studies mean for would-be-moms who have undergone IVF treatment? There's no point in panicking, but if you're concerned about air pollution in your neighborhood, you may want to talk to your health care provider about the best ways to protect yourself and your baby ... so that you can both breathe a little easier.

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