How Much Is Enough? Understanding Newborn Stomach Size and Milk Intake in the First Days

Why Your Baby’s Tiny Tummy and Your Early Milk Supply Are Perfectly Matched

As a new parent, it’s completely normal to worry whether your baby is getting enough to eat—especially in those early days of breastfeeding when everything feels new, fragile, and sometimes confusing. But here’s some reassuring news: nature has thought of everything.

Your newborn’s stomach is remarkably small—and your body is producing just the right amount of early milk, called colostrum, to match. Let’s break it down.

Your Newborn’s Stomach Size: Tiny But Mighty

In the first days after birth, your baby’s stomach is about the size of a cherry (around 5–7 mL per feeding). By day 3, it grows to about the size of a walnut (22–27 mL), and by the end of the first week, it’s closer to an apricot (45–60 mL). That’s still pretty small!

This is why your body doesn’t produce large volumes of milk right away. Instead, it produces colostrum—a nutrient-rich, antibody-packed early milk that’s perfectly portioned for your baby’s tiny tummy.

What If You Don’t See Milk When You Express?

It’s common to worry if you try hand-expressing in the early days and see little to no milk come out. Here’s the truth:

👉 That’s normal (!!).

Colostrum is thick, concentrated, and produced in small amounts—sometimes just a few drops at a time. It might not look like much, but it’s exactly what your baby needs. Don’t be discouraged if you don’t see anything. Your body is working.

How Do You Know Baby Is Getting Enough?

Instead of focusing on how much milk you see, focus on these signs that your baby is feeding well:

• Frequent feeding: 8–10 times in 24 hours is typical. Breastfeeding works on a supply-and-demand system, so the more frequently milk is removed (by baby, hand expression, or pumping), the better your supply will build.
• Swallowing sounds: You may hear soft “ka” sounds during feeds, indicating baby is swallowing.
• Diaper output: Expect at least one wet diaper on day 1, two on day 2, and increasing each day. By day 5, you should see at least 6 wet diapers and several stools a day.
• Baby seems content after feeds and is alert and gaining weight appropriately.

If you're ever in doubt, connect with a lactation consultant or your pediatrician—they're there to help.

Trust the Process (Even When It Feels Uncertain)

It’s easy to second-guess your body in those early days, especially when milk isn't pouring out or your baby wants to nurse constantly. But remember: this is exactly how it’s supposed to work. Frequent, effective milk removal is what signals your body to increase supply.

Whether your baby is breastfeeding, or you’re hand-expressing or pumping, regular stimulation and removal—at least 8–10 times in 24 hours—keeps things on track.

Final Thoughts

Your newborn’s stomach is small, your early milk supply is enough, and you’re doing better than you think. Trust your body, trust your baby, and don’t be afraid to ask for support.

In those early days, every drop of colostrum is gold—and so are you.

Questions or concerns about feeding in the early days?  Reach out to me, your local lactation consultant, for any and all of your questions!

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