From the YummyYucky team, founded by Nancy Nash
What are the brick-red or orange stains in my baby's diaper?
It is day two, you are running on ninety minutes of sleep, and there is what looks like dried blood in the diaper. This is one of the most reliably terrifying moments of the first week, and it has one of the most boring explanations in all of newborn care: urate crystals, a stain so classic that midwives call it brick dust. It is almost certainly not blood, and in the first few days it is not a problem.
What urates actually are
Newborns arrive with naturally high uric acid levels, and in the first days their urine is concentrated, because milk volume is still ramping up. Concentrated urine can tint a diaper pink on its own, and the urate salts in it can crystallize into a powdery pink, orange, or brick-red stain, usually toward the front of the diaper where urine lands. Pediatric guidance is explicit that this first-week stain is usually concentrated urine, not blood, and NHS midwifery guidance describes urates the same way: tiny brick-dust crystals that disappear once regular feeding is established.
Why days 1 to 3 are normal
The first days run on colostrum: small volumes by design, matched to a marble-sized stomach. Small volumes in mean concentrated urine out, which is exactly the environment urates like. So a brick-dust stain on day one, two, or three, in a baby who is waking to feed and producing wet diapers on schedule (roughly one more each day: 1 on day one, 2 on day two, and so on), is a normal snapshot of a system still filling up. As milk comes in around days three to five and urine dilutes, the stains fade and usually vanish.
Past day 3 or 4: it becomes a feeding question
Persistence is the part that matters. If brick-dust stains keep appearing once milk should be in, that says urine is still concentrated, and the usual reason is that not enough milk is going in yet. That is not a catastrophe; it is an early, useful signal, and the response is concrete:
- Count wet diapers against the day-by-day rule in newborn diaper counts: by day five, 6 or more heavy wet diapers a day is the reassuring number
- Audit the feeding: frequency, swallowing you can hear, and the other signals in is my baby getting enough milk?
- Tell your pediatrician or midwife: persistent pinkish staining plus a low diaper count is exactly what the early weight checks exist to catch, and a feeding tune-up (often just a latch fix or more frequent feeds) usually resolves it quickly
Urates vs blood: how to tell
Urates: powdery, dry-looking, pink to orange to brick-red, sitting in the urine zone at the front of the diaper, with nothing on the baby. Blood: red and wet-looking, streaked in or on the stool or around the anus. The distinction matters because the responses differ: first-week urates are a shrug or a feeding check, while blood in a young baby's diaper always deserves a call. If what you see is in or on the poop itself, or you are not sure, treat it as blood and read blood in a baby's diaper.
The wet-diaper count is the answer machine
Notice that every fork in this guide resolves the same way: check the wet diaper count. That number is the single clearest signal that feeding is working, and it is much easier to read off a log than to reconstruct at 3am. Logging each diaper in YummyYucky takes one tap, wet, dirty, or both, so "are we actually at six today?" has a real answer, and if a stain does persist, you walk into the pediatrician's office with the exact numbers they will ask for first.
No account needed to start: tap wet, dirty, or both, and the daily count adds itself up.
Log a diaper in ten seconds →Related reading
See how many diapers a newborn should have, is my baby getting enough milk?, and blood in a baby's diaper.
This is general information, not medical advice. If pinkish or brick-red staining persists past the first few days, if wet diapers are below the expected count, or if your baby is very sleepy or hard to wake to feed, contact your pediatrician or midwife, and in an emergency contact emergency services.
Frequently asked questions
What are urate crystals in a baby’s diaper?
Uric acid crystals from your newborn’s urine, showing up as a pink, orange, or brick-red powdery stain, usually toward the front of the diaper. Newborn urine is concentrated in the first days while milk volume is still ramping up, and the urate salts in it can crystallize in the diaper, leaving a stain that looks alarmingly like dried blood but is not.
Are urate crystals normal in a newborn?
In the first few days, yes, very. They are a classic first-week finding, common enough that midwives and pediatricians treat a stain in days 1 to 3 as routine, and they fade as feeding volume climbs and urine dilutes. As long as your baby is producing wet diapers on the expected day-by-day schedule, an early brick-dust stain is not a problem.
What if urate crystals keep appearing after day 3 or 4?
Then the stain stops being a curiosity and becomes a feeding question. Persistent urates mean urine is staying concentrated, which is usually a sign the baby is not yet getting enough milk. Count wet diapers against the day-by-day rule, watch feeding closely, and contact your pediatrician or midwife; the fix is nearly always more effective feeding, sorted early.
How can I tell urate crystals from blood in the diaper?
Location and texture. Urates are a powdery, dry-looking pink-to-orange stain in the urine area at the front of the diaper, with no source on the baby. Blood is red, tends to streak in or on the stool or appear around the anus, and looks wet rather than dusty. If red appears in or on the poop itself, treat it as blood and call; if it is a brick-dust stain in the pee zone in week one, it is almost certainly urates.
Do urate crystals mean my baby is dehydrated?
Early on, they mean concentrated urine, which is expected while milk comes in, not a diagnosis. The dehydration question is answered by the wet diaper count and the baby: roughly one more wet diaper each day in the first week, 6 or more from about day five, alongside a baby who wakes to feed. Too few wet diapers, a very sleepy baby, or urate stains persisting past the first days are the combination that warrants a same-day call.
Sources
- American Academy of Pediatrics (HealthyChildren.org): Baby's First Days: Bowel Movements & Urination
- Milton Keynes University Hospital (NHS): Baby Checks (postnatal care)
- American Academy of Pediatrics (HealthyChildren.org): How Often and How Much Should Your Baby Eat?
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Start tracking for freeLast updated September 2026. Next review December 2026. How we write these: built from current published guidance from the AAP, CDC, FDA/EPA, NIAID, WHO, and other pediatric and public-health authorities, with sources cited on the page. See our editorial and medical policy for how we research, source, and update these, and how we double-check the food advice.
This is general information, not medical advice, and is not individualized for your baby. Always talk to your pediatrician about your baby's diet, introducing allergens, and any reaction. In an emergency, contact emergency services.
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