When Does Baby Reflux Go Away? Age by Age

For most full-term babies, reflux is gone between 9 and 12 months. It begins at about 2 to 3 weeks of age, peaks between 4 and 5 months, and improves sharply after 6 months once the baby can sit up. MedlinePlus stretches the tail a bit further, describing routine spitting up as ending around 12 to 14 months and calling it unusual past 18 months.

The curve most parents are actually on

Age	What is typical
2 to 3 weeks	Reflux starts; spit-up appears after feeds
4 to 5 months	The peak — frequency and volume are at their highest
6 months	Clear improvement as sitting and solids arrive
9 to 12 months	Resolved in most full-term babies
12 to 14 months	Outer edge of routine spitting up (MedlinePlus)
Past 18 months	Unusual; worth a conversation

The peak is the part worth internalizing. Parents who reach four months convinced things are deteriorating are almost always standing on top of the curve, not at the start of a slide. What that stage looks like day to day is described in baby reflux symptoms.

Why it fades on its own

Three things change at once, and none of them requires treatment.

1. The valve matures. The lower esophageal sphincter tightens its grip over the first year.
2. The baby stops living horizontally. Sitting, then standing, puts gravity to work.
3. Food gets thicker. Milk refluxes more easily than the purees and solids that replace part of it.

When the calendar is not the answer

Two situations break the timeline. The first is a baby whose reflux never improves — the NASPGHAN and ESPGHAN guideline recommends consulting a pediatric gastroenterologist when regurgitation has not resolved by 12 to 18 months, or sooner if warning signs appear. The second is the baby whose reflux was never the simple kind to begin with: poor weight gain, refusal to feed, blood or green color in the vomit, wheezing or coughing. Those are evaluated on their own schedule, not the calendar’s.

Preterm infants are their own case; the AAP’s 9-to-12-month figure is stated for full-term babies, and prematurity raises the odds of reflux disease.

Waiting it out without making it worse

Nothing about the wait requires changing where a baby sleeps. Back, flat, firm surface, every nap and every night — the reflux does not buy an exception, and the products sold to create one were banned in the United States. The steps that do help sit around the feed itself, and they are collected in best positions for baby reflux.

This content is informational and does not replace medical consultation, diagnosis, or treatment. See also silent reflux in babies and baby reflux symptoms.