At some point your newborn is bound to catch a bug. Because a fever can be dangerous, it's important to keep careful track of your baby's temperature when she's sick and to call the doctor right away if it climbs to 100.4 degrees Fahrenheit or higher during the first three months.

How to take a temperature?
The American Academy of Pediatrics advises against using mercury thermometers because the glass can break, releasing potentially toxic mercury vapor. Likewise, your baby's too young to hold a thermometer in her mouth, and her ear canals are too narrow for an ear thermometer. Other methods and thermometers are unreliable. The best option: taking a RECTal temperature with a digital thermometer.

1. Clean your hands and the thermometer (follow the cleaning instructions on the package), then dab a little K-Y or petroleum jelly on the bulb and press the "on" button.

2. With your baby lying facedown across your lap or on a firm, comfortable surface, gently spread her buttocks apart with one hand and use the other to hold the thermometer between your middle and index fingers.

3. Gently insert the tip of the thermometer a half-inch to one inch into your baby's RECTum. Hold it in place until you hear the beep, anywhere from 30 seconds to two minutes later. Then slowly withdraw the thermometer to read it.

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