How Much Breast Milk Does a Newborn Need? What Parents Actually Need to Know

“How much milk is my baby getting?” is one of the most common questions new parents ask, and it’s a fair one. With a bottle you can see the ounces. At the breast, you can’t. The good news is that you don’t need to count ounces to know your baby is doing well.

Why Newborns Need So Little at First

Babies spend nine to ten months floating in fluid, so they are born carrying extra fluid. In the first day or so of life, their bodies adjust as they transition to life outside the womb. Fluids shift, which helps with stooling and appetite. This is why small amounts of colostrum are so important.

Colostrum is made up of many things, and sugar is a primary source. That sugar fuels your baby’s brain and body for the demanding new work of life outside the womb, including regulating brain activity that controls vital signs like temperature, heart rate, and breathing.

Once a healthy baby begins regular stooling, around day 1 to 2, their appetite slowly increases and they begin to ask for more. Giving them a little more each day is how your body builds a milk supply made just for them, matched to their body and their genetic makeup. That is part of what makes breast milk so remarkable. If a baby can’t latch or feed, we ask mothers to pump, so they can help bring in this milk that is made for their baby.

Newborn Stomach Size, Day by Day

• Day 1: about the size of a cherry, holding roughly 5-7 mL (about 1 teaspoon) per feeding

• Day 3: about the size of a walnut, holding roughly 22-27 mL (about 0.75-1 oz) per feeding

• Day 7 (1 week): about the size of a large egg, holding roughly 45-60 mL (about 1.5-2 oz) per feeding

These figures describe healthy, full-term babies. Every baby is a little different, so use them as a general picture, not a target.

Babies born early or with medical conditions may have different feeding needs and may not be able to ask for food on their own. If your baby was born early or has a medical condition, follow the feeding plan from your baby’s care team and ask your pediatrician or IBCLC what amounts are right for your baby.

Watch Your Baby, Not the Clock or the Ounces

Healthy, full-term babies are good at regulating their own intake. Feedings will vary from one to the next, just like your own meals do. These signs tell you far more than a measurement:

• Your baby feeds regularly, usually 8 to 12 times in 24 hours in the early weeks (see our guide: How Often Should a Newborn Feed?)

• You hear or see swallowing during feeds

• Your baby seems relaxed and satisfied after most feedings

• Diapers increase over the first week and stay regular

• Your baby is alert and has periods of being awake and content

For the full checklist, read: How to Know if Your Baby Is Getting Enough Breast Milk: 10 Signs to Look For.

Do I Need to Track Ounces?

Most breastfeeding parents don’t. Your baby’s cues, diapers, and weight checks with your pediatrician tell the real story. If you are pumping or giving bottles, your IBCLC can help you work out a bottle size that fits your baby, your routine, and your supply.

Why Does My Baby Seem Hungrier Some Days?

Growth spurts and cluster feeding are normal. Your baby may want to feed more often for a day or two, which helps your body make the milk they need. If it lasts longer than a few days or you are worried, reach out.

When to Call for Help

Contact your pediatrician or an IBCLC if:

• Your baby is hard to wake for feeds or seems very sleepy

• Your baby seems unsatisfied after most feeds

• You are seeing fewer wet or dirty diapers than expected

• Feeding is painful for you

• You are worried about weight gain or your milk supply

You don’t have to wait for a problem. A lactation consultant can watch a feeding and give you a plan based on your baby, not an average.

The information in this article applies to healthy, full-term babies. Babies born early or with medical conditions can have different feeding needs, so please follow the plan from your baby’s pediatrician or care team.

This article is for general education and is not medical advice. Always talk with your baby’s pediatrician or an IBCLC about your baby’s specific needs.

Insurance & Booking

Insurances we work with include Aetna, Cigna, United Healthcare (UHC), UMR, Meritain, Anthem, Wildflower, The Lactation Network, Curative, Tricare Select, BCBS of Texas, Blue Cross Blue Shield PPO, VA CCN, and some HMO plans. Check your specific plan at lactationloop.com/insurance-information. Sliding scale service is available upon request.

Book a visit: lactationloop.com/services, or call/text 941-254-2502

Written by Jennifer Chivas, RN, BSN, IBCLC, Founder, Lactation Loop