Breastfeeding your baby, although rarely easy, is fairly straightforward. Your milk is naturally at the perfect temperature for your baby, and you don't have to worry about heating or cooling it. When you start expressing your breast milk, however, it leaves it bit more up to question. Once your milk has been frozen or chilled, you'll need to know how to check the temperature of your breast milk, to make sure that it's not too hot or too cold.
According to Baby Center, the best way to warm your baby's bottle is by running it under warm water or sitting it in a bowl of warm water until it thaws or comes to a warm temperature. You should never microwave or boil your baby's bottle, which could lead to scalding the milk, and damaging the healthy proteins in the milk, an article from Medela noted. But how do you know exactly what temperature your baby's milk should be? The balance between too hot, warm, and too cold can be tricky to strike.
According to Baby Gear Lab, breast milk that is warm but not yet hot (the ideal temperature for babies,) is about 104 degrees. By the time the milk reaches 125 degrees, it's considered hot and the properties of the breast milk begin to deteriorate.
To test the temperature of your baby's bottle, She Knows suggested sprinkling a bit of the milk on your wrist, which is the most sensitive part of your arm. The milk should feel warm, but definitely not too hot or too cold. Many babies won't drink milk that is too cold, and milk that is too hot could scald your little one. Simply feeling the bottle with your hands is an inaccurate way to test the temperature of the milk and could lead to giving your baby milk that is overly warm or only warm in patches.
Once you've run the bottle under warm water or submerged it in a warm bowl, give the bottle a swirl to properly mix it all up, and then put a few drops on your wrist for the best indicator of whether it's too hot, too cold, or just right.