How to Freeze Breast Milk
To freeze expressed breast milk, start by portioning it out into 2 to 4 fluid ounce servings to avoid waste. Put the milk into BPA-free food-grade containers, glass bottles with tight-fitting lids, or bags designed for storing breast milk. Label each container with the date that you expressed the milk since you'll want to use the oldest milk first. If you're sending the milk with your child to a babysitter or daycare, make sure to write their name on the label too. Place your containers of milk in the back of your freezer where it's coldest to keep the milk from forming harmful bacteria. Use the milk within 6 to 12 months if it's kept in your freezer.
 with a pump or by hand. Express the milk How you express your breast milk is up to you. Some women prefer electric pumps, some use manual pumps, and others opt to express their milk by hand. Whichever method you use, wash your hands with soap and water, then settle into a quiet comfortable place and try to relax to promote a stronger milk flow. Before you use a breast pump, wash any parts of the pump that come into contact with your skin or the milk, including any tubes. If you're having trouble with your milk flow, you can gently massage your breasts or nipples, lay warm compresses over your breasts, or imagine holding your baby. All of these can help stimulate milk production. Portion the milk into 2–4 fluid ounces (59–118 mL) servings. To minimize waste, freeze your breast milk in smaller portions. If you think your baby will need more than 2–4 fluid ounces (59–118 mL) at a time, thaw out 2 containers of milk and leave one in the refrigerator until you need it.. As your baby gets bigger, you can increase the servings to 4–5 fluid ounces (120–150 mL) if you like, or you can continue using multiple containers at each feeding. The smaller containers will thaw out faster, so defrosting 2 containers per feeding may be more efficient than thawing out 1 large one. As you're portioning out the milk, don't fill the containers to the brim, since breast milk expands as it freezes. Leave at least 1 inch (2.5 cm) of headroom in each container to prevent it from bursting in the freezer. Store the milk in BPA-free food-grade containers. You may want to use glass bottles with tight-fitting lids, hard-sided plastic containers, or special bags designed for storing breast milk. If you choose to use plastic, though, you should check the bottom of the container for a recycling symbol containing the number 7. This may indicate that the plastic contains the harmful chemical BPA, which can seep into the breast milk. Even bags intended for breastmilk can tear, so you may want to place them inside another hard-sided container until the milk is frozen. Only use containers which are specifically intended for storing breast milk. Label each container with the date. Apply a waterproof label to the container if it doesn't already have one, and write the date that you expressed the milk on the label in waterproof ink. You'll always want to use the oldest milk first, and having a clearly-written label will help you stay organized. If you're sending the milk with your child to a babysitter or daycare, include the child's name on the container so it doesn't get mixed up with anyone else's. Place the container in the back of the freezer. The back of the freezer is where the temperature is the coolest, so the milk will drop to a safe temperature more quickly. If you store the milk in the door or the front of the freezer, it might not get as cold as it needs to be in order to kill any harmful bacteria. This is because cold air escapes the freezer each time the door is opened, leaving the front of the freezer slightly warmer. Try placing the new breast milk behind what's already in the freezer, so it will be easier to use the oldest milk first. Use the milk within 6-12 months. Frozen breast milk can be used for up to 12 months if it's kept at 0 °F (−18 °C). However, since the vitamin C in milk breaks down over time, it's best to use it within about 6 months. Your body produces different antibodies and nutrients for your baby over time, so it's best if they can have fresh milk. However, in cases where this isn't an option, using the oldest milk first will help prevent having to give them older milk if you run out. Thaw the oldest milk first. If you've labeled the milk, it should be easy to tell which milk has been in the freezer the longest. This will help make sure that none of your breast milk is wasted because it expired. If you come across milk that's been in the freezer much longer than the rest, it's best to use it right away or throw it out, since breast milk loses nutrients over time. Place the frozen container in the fridge to thaw the milk overnight. The easiest way to thaw out frozen breast milk is to let it slowly come up to temperature in the refrigerator. Each night, take out the milk you'll need for the next day and place it into the refrigerator so it will be ready when you wake up. To make sure the milk doesn't leak in your fridge, place the container or bag of breast milk in a shallow, flat-bottomed container, like a Tupperware dish. Do not thaw out the milk at room temperature, as this could allow for the growth of harmful bacteria. Place the frozen milk in warm water if you need to thaw it out faster. If you don't have time to thaw out the milk overnight, you can use warm–not hot–water. Either place the container of milk under warm running tap water, or let it sit in a bowl of warm water until it thaws out. This method will typically thaw out a 2–4  fl oz (59–118 mL) container of milk in about 10-15 minutes, depending on the container. You can also do this to warm the milk before you feed your baby, although breast milk can be served cold or room temperature. Never heat breast milk in the microwave. Not only can it affect the nutritional content on the milk, but it may leave hot spots which can cause serious burns to an infant. Shake the container of milk after it has thawed. Sometimes frozen breast milk can separate, forming a milk layer and a fat layer. This is perfectly normal, and it doesn't mean that the milk has spoiled. Simply shaking the container will help mix the fat back into the milk. When the milk separates, it sometimes changes colors, as well. As long as the milk is less than a year old and has maintained a constant temperature of 0 °F (−18 °C), it should still be good. However, if the milk has a strong, unpleasant smell, you should discard it. Discard milk that isn't used within 24 hours. Once it's been thawed out, the milk will keep in the refrigerator for about a day. After that, you should throw it out. Never refreeze breast milk that has already been frozen and thawed out. Toss out the milk after 1-2 hours if it has been kept at room temperature. 
 with a pump or by hand. Portion the milk into 2–4 fluid ounces (59–118 mL) servings. Store the milk in BPA-free food-grade containers. Label each container with the date. Place the container in the back of the freezer. Use the milk within 6-12 months. Thaw the oldest milk first. Place the frozen container in the fridge to thaw the milk overnight. Place the frozen milk in warm water if you need to thaw it out faster. Shake the container of milk after it has thawed. Discard milk that isn't used within 24 hours. 