If you’re a mother who has been breastfeeding on request, you probably haven’t had to measure bottles of breast milk or worry about the number of ounces. It can be a bit daunting to shift your attention to how much milk you produce and try to figure out how many ounces you will need to have ready for your baby each day.

The trick is to store your milk in small quantities, about two ounces each. This helps you determine how much your baby needs at each feeding while also reducing waste (it is best to discard whatever breast milk remains in a bottle once thawed and offered to your baby, although some caregivers use the leftover milk to complete the feeding if it was interrupted). Ask your child’s caretaker to keep a log of each of the feeding times and amounts for the first week or two, as you and your baby adjust to this new schedule. Based on this information, you can determine whether you want to stick with two-ounce servings or move to larger amounts.

Generally, in an eight- or nine-hour day, you can expect your baby to take between 8–15 ounces of milk. You may find that your baby takes less of your milk from a bottle during the day, choosing to breastfeed more in the mornings and at night when you are together. Because the composition of your milk will change in response to your baby’s needs as she grows, and because she can digest your milk easily, the amount of milk your baby will need during the first three to six months may remain relatively stable. An increase in her demands for milk during the day could indicate that the care provider is overfeeding her, your baby is sleeping more at night, or she is breastfeeding less in the mornings and evenings when the two of you are together.

Once your baby starts solid foods (around 6 months of age), the amount of milk she consumes will probably decrease, but breast milk should still be an important part of her diet for at least the first year.