The Three Stages of Your Body Making Milk

an interactive guide

The Three Stages of Your Body Making Milk

Milk-making isn't a switch that flips at birth — it's a process that starts during pregnancy and settles into a rhythm long after. Scroll through what's happening, stage by stage.

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Stage 1 · Around week 16

Your body starts making milk before your baby arrives.

Around week 16, the milk-making cells in your breasts or chest start getting ready. With stimulation, some parents can hand-express drops of colostrum by late pregnancy. Some may even notice their nipples leaking on their own. It's totally normal to not notice anything at all.

Clinical Name Secretory differentiation · Lactogenesis I‍
‍

Highin pregnancy

↓

Lowafter birth

Holding the brake — flip to release.

Birth · Progesterone drops

Birth flips the switch “on.”

During pregnancy, the placenta makes high levels of progesterone, which acts like a brake on full milk production. When your baby and placenta are born, progesterone drops fast — and that drop releases the brake. This is why delivering the whole placenta matters for your supply.

Highin pregnancy

↓

Lowafter birth

Holding the brake — flip to release.

Stage 2 · 2–4 days after birth

Your milk “comes in”? More like… it just “gets flowing.”

With the brake off, your body not only shifts into serious milk-making — it starts fully releasing milk. This is the "milk coming in" most people have heard about. It usually happens between 30 and 72 hours after birth, on day 2 or 3. It's common for the breasts or chest to feel fuller, firmer, or warmer. This “big flow” still produces what can seem like a small amount of colostrum — but that's the right amount for a newborn's bead-size stomach.

Clinical Name Secretory activation · Lactogenesis II‍

Sometimes people experience a slower start. The early flow of milk may may sometimes be delayed or softened by stress, medication, and/or delayed hormonal signals. It's usually temporary and may be remedied by removing milk more often. Whenever in doubt, reach out to your care team — in particular a lactation consultant (IBCLC) — for support.

Stage 3 · Around day 10

Then it becomes supply and demand.

From here on, your supply runs on a simple loop: the more milk that's removed, the more your body makes. Milk left sitting in the breast actually signals your body to slow down. Frequent, effective removal — by baby or pump — is what keeps things going.

Clinical Name Galactopoiesis

Whenever you wean

There's no one right time to wean.

Both the World Health Organization and the American Academy of Pediatrics suggest feeding your milk on its own for about the first 6 months, then continuing alongside other foods up to age 2 or beyond — for as long as it works for you and your baby.

But guidelines are a starting point, not a deadline. When and how you wean is a personal decision — it depends on your body, your baby, your life, and what you want. There's no finish line you have to reach, and no amount of milk that's “too little” to count. However long you feed, and however you choose to stop, that choice is yours.

WHO
Milk alone for ~6 months, then continued alongside foods to age 2+.

AAP
Same guidance, updated in 2022 — 2 years or beyond, as mutually desired.

The Educated Birth