Preparing formula: 8 steps

Whichever formula you choose, proper preparation and refrigeration are essential. Follow these steps:

•  Step 1: Sterilize your bottles and nipples. Before you bottle-feed your baby, whether with formula or with expressed breast milk, sterilize bottles and nipples in a dishwasher or in a pot of boiling water for five minutes.

•  Step 2: Check your water. Powdered and liquid concentrate formula must be mixed with water. Most formula manufacturers recommend using bottled water or boiled tap water. However, if the water you drink comes from a municipal water supply, you can be fairly confident that it's safe without boiling. Well water can sometimes pose a problem. If you have any doubts about your drinking water, check with your local water utility or have your well water tested.

•  Step 3: Wash your hands and utensils. Before preparing formula, wash your hands. Be sure all the utensils you'll use have been washed and rinsed. If you use canned formula, it's a good idea to keep a separate opener just for formula cans. Use a clean towel or napkin to wipe the top of the can before you puncture it.

•  Step 4: Measure the formula. Don't take shortcuts in measuring. If you're using powdered formula, fill the scoop provided and shave off any excess formula with the flat of a knife. Don't use a spoon or any other curved surface, and don't pack the powder unless directed to do so in the instructions on the can. You can pour liquid concentrate directly into a bottle with ounce levels marked on its side, or you can use a measuring cup. Always hold the bottle or the cup to eye level to check the amount. Make sure that the quantity is exactly level with the correct measurement mark.

•  Step 5: Mix the formula. Always mix powdered or concentrated formula with the exact amount of water the manufacturer specifies on the label. Use an accurate measuring scoop or cup. Too much or too little water can be harmful to your baby. If the formula is too diluted, your baby won't get enough nutrition to meet growth needs or to satisfy hunger. Formula that is too concentrated can be even more dangerous. It puts a serious strain on your baby's digestive system and kidneys and can lead to dehydration.

•  Step 6: Prepare the bottles. If you prepare and fill several bottles at one time, place any that aren't for immediate use in the refrigerator. Keep bottles refrigerated until your baby is hungry. Any bottles that haven't been used within 24 hours of mixing may be spoiled, even if they've been refrigerated. To be safe, pour them down the drain.

•  Step 7: Heat things up. It's unnecessary to warm bottled formula before you give it to your infant. Babies prefer formula at room temperature. Newborns and fussy eaters may refuse cold bottles.

To warm chilled formula, place a filled bottle in a bowl or pan of hot water and let it stand for a few minutes. When your baby starts to stir after a nap, take a prepared bottle out of the refrigerator and start to warm it. By the time your baby is ready to eat, the milk will be ready. Do not warm baby bottles in a microwave oven because the fluid will heat unevenly, creating hot and cold spots.

•  Step 8: Test the temperature before giving your baby a warmed bottle. Shake the bottle after warming it. Then turn it upside down and allow a drop or two of formula to fall on your hand. It should feel comfortable and barely warm.

Once you warm a bottle, never put it back in the refrigerator — even if your baby goes back to sleep before starting the bottle. Any formula left over in a bottle should go down the drain, not back in the refrigerator.

New babies have few defenses against germs, as it takes awhile for them to build up immunity. Preparing and storing formula safely will help minimize the chance of contamination.