When does newborn cone-head go away?

The cone-shaped head a lot of newborns are born with looks dramatic in the first photos and is gone by the time they meet their first visitor. Here is what causes it, when it resolves, and the head shape concerns that come up after the first month.

Why newborn heads are shaped this way

A baby's skull is made of separate bone plates connected by flexible joints called sutures. The plates can shift and overlap during delivery — that's what makes a vaginal birth possible at all. The result is sometimes a slightly cone-shaped or asymmetric head.

The plates move back into a rounded shape within a few days to a couple of weeks. The soft spots (fontanelles) on top and back of the head stay flexible for months, but the dramatic cone shape fades fast.

Cone-head timeline

Day 1 to 3: most noticeable

The cone or oval shape is at its peak in the first 72 hours. You may also see some bruising or swelling on the scalp (called a caput or cephalohematoma — see below). This is the part of birth they don't put in the pamphlets.

Day 4 to 7: visibly rounder

The skull plates start settling back. By the end of the first week, most babies look noticeably more round.

Week 2 to 4: normal newborn head shape

The cone is gone. You may still see slight asymmetry depending on which side baby sleeps on, but it's no longer pointy.

Cone-head vs other birth-related bumps

Caput succedaneum (caput)

Soft puffiness or swelling on the top of the head from pressure during delivery. Feels squishy, crosses the suture lines. Resolves in a few days. No treatment needed.

Cephalohematoma

A pocket of blood between the skull bone and its covering, caused by a blood vessel breaking during delivery. Feels firm and bouncy, does not cross suture lines (stays on one side of the head). Takes longer to resolve — usually 2 weeks to 3 months. Sometimes leaves a small calcium deposit you can feel for a few months. Generally harmless. Sometimes contributes to jaundice as the blood breaks down.

Bruising

Discoloration on the scalp, ears, or face from forceps or vacuum-assisted delivery. Resolves in 1 to 2 weeks like any bruise.

Plagiocephaly: flat head from sleep position

The other head-shape concern is flatness that develops after the first few weeks of life. Since the AAP started recommending back-sleeping in the 1990s (which has cut SIDS dramatically), more babies develop a flat spot on the back or one side of their head, called positional plagiocephaly.

What it looks like

• One side of the back of the head is flatter than the other.
• One ear may sit forward of the other when you look down at the head from above.
• The forehead on the flat side may bulge slightly.

Why it happens

Newborn skull bones are soft. Babies spend a lot of time on their backs (correctly, for safe sleep). If they consistently turn their head to one side, gravity flattens that spot. Babies who have tight neck muscles (torticollis) almost always develop plagiocephaly because they can only turn one way.

How to prevent and fix flat spots

Most cases of positional plagiocephaly improve with simple repositioning. The earlier you act, the easier the fix.

Tummy time, lots of it

Aim for 3 to 5 short sessions per day, totaling 15 to 30 minutes by 7 weeks. Tummy time keeps weight off the back of the head, strengthens neck muscles, and helps prevent flat spots. More on this in our tummy time guide.

Repositioning during sleep

Always back to sleep, but alternate which direction baby's head naturally turns. If they tend to look left, put their head at the opposite end of the crib at the next nap so they look right toward the door or window.

Vary positions when awake

• Wear baby in a soft carrier or wrap (when awake) for some of the day.
• Side-lying play on a blanket on the floor.
• Limit time in car seats, swings, and bouncers once you're out of the car. Stretches in seated equipment add up.

If you suspect torticollis

If baby strongly prefers one side and physically resists turning the other way, that's torticollis — tight muscles on one side of the neck. It's common, easy to treat with a couple of physical therapy sessions, and the earlier the better. Mention at your 2-month well visit if you notice it.

When a helmet is recommended

Most cases of positional plagiocephaly resolve with repositioning and tummy time. Helmets (cranial remolding orthoses) are reserved for moderate to severe cases that haven't responded to repositioning by 4 to 6 months.

If a helmet is recommended:

• Best window for fitting: 4 to 8 months (when the skull is still growing fast).
• Worn 23 hours a day, refitted every few weeks.
• Average treatment: 3 to 6 months.
• Not all insurance covers it. Costs $1,500 to $3,500 without coverage.

Craniosynostosis (rare but important)

Premature fusion of one or more skull sutures is called craniosynostosis. It's rare (about 1 in 2,500 births) but it's different from plagiocephaly and needs surgical evaluation. Signs:

• A ridge you can feel along one of the skull suture lines.
• Head shape that's not just flat but elongated, narrow, or pointed.
• Asymmetry that gets worse over time, not better.
• A soft spot that closes very early (before 6 months).

Pediatricians check head shape at every well visit. They'll catch this. If you're worried about a suture ridge, ask at the next visit or send a photo via your provider's portal.

When to call your pediatrician

• Cone shape from birth is not improving after 2 to 3 weeks.
• You notice persistent flat spots after 2 months.
• Baby strongly prefers one head position and resists the other (suggests torticollis).
• The soft spot bulges, is very sunken, or feels firm and not soft.
• Baby's head looks elongated, narrow, or asymmetric in a way that worsens.
• You can feel a hard ridge along a suture line.