Posterior closes time and head circumference - #11294
My babyboyis 3 months 28 days old his head circumference 43 cm is it ok and his posterior fontanelle bulging when his crying and it is normal in upright position other than myboy is active no feeding issues healthyweight gain
100% Anonymously
No sign-up needed.

Doctors’ responses
Head circumference is 1 cm more but not to worry Baby is feeding and thriving well Posterior Fontanelle Bulging
When babies cry, cough, or strain, it’s normal for the fontanelle (soft spot) to look temporarily full or bulging.
It should look flat/soft when calm, upright, and not crying which you said is the case
That’s considered normal
If it bulges continuosly then you need to visit peadtrician
At just over three months, a head circumference of 43 cm for a baby boy generally does fall within normal range, but it’s always essential to consider the individual’s growth curve and trends. Head size alone doesn’t give the complete picture; regular growth monitoring by your pediatrician is key. The posterior fontanelle, which is the soft spot on the back of a baby’s head, typically closes by about 1 to 3 months of age, but can vary. The fact that it bulges when he’s crying and returns to normal when upright isn’t typically a red flag. Bulging of the fontanelle when a baby is crying can be a normal response due to increased intracranial pressure from crying. What matters more is if it remains bulging when he’s calm, which could indicate increased pressure inside the skull and might need further evaluation. Since your son is active, feeds well, and is gaining weight healthily, those are all positive signs, but it’s still wise to have his pediatrician confirm that everything progresses as it should. Ensure you attend regular check-ups to track his growth and development, this helps rule out any underlying concerns. If you ever observe persistent bulging, unusual irritability, vomiting, or other concerning symptoms, that would be the appropriate time to seek more immediate medical advice. Babies can exhibit a wide range of normal variations, but it’s always best to discuss with your healthcare provider who can oversee and guide you through his specific needs as he grows.
100% Anonymously
Get expert answers anytime, completely confidential. No sign-up needed.
About our doctors
Only qualified doctors who have confirmed the availability of medical education and other certificates of medical practice consult on our service. You can check the qualification confirmation in the doctor's profile.