A: Microwave ovens use a form of radiation that heats food by causing water molecules within the food to vibrate. If the microwave door has a good seal, only items within the oven are affected by the radiation. If you think your microwave could be leaking, either because the door is warped or the oven appears to function when the door is open, it's unwise to use it. It's also advisable to stand several feet away from the microwave when it's in use.

When you microwave food, transfer it to containers made of ceramic or glass rather than plastic. Some plastic containers and plastic wraps contain chemicals (dioxins) that can seep into your food during the microwave process. These chemicals should not be consumed during or after pregnancy.

Also, remember that a microwave can heat foods unevenly. Avoid overheating beverages, stir foods before consumption and carefully test the temperature before eating.