Despite the hardened layer of cheese on top, that slice of lukewarm pizza is calling your name. Sound familiar? In a recent survey from the ConAgra Foods Foundation, 36 percent of people admitted to eating leftover pizza from the night before  -- even if it hadn't been refrigerated. If you're pregnant, however, crave with care. What seems like a harmless guilty pleasure may actually be dangerous to you and your unborn baby.

If left unrefrigerated for more than two hours, bacteria (such as salmonella) can collect on those delicious cheese and meat toppings and cause food poisoning, says Julie Upton, R.D., a spokesperson for the American Dietetic Association. While anyone is susceptible to food poisoning, a food-borne illness contracted by a mom-to-be can cause birth defects in her baby.

Take a few simple steps to prevent unnecessary illness:

• If the pizza has been sitting out for more than two hours, toss it.
• Immediately refrigerate leftover pizza and be sure the temperature in the fridge is set below 40 degrees.
• Use an airtight shallow container for storage to help the pizza cool faster in the fridge.

---