At what age does the posterior fontanelle normally close?

• A 18 months
• B 3 to 4 months
• C 9 to 12 months
• D At birth or within the first few weeks ✓

Explanation

The posterior fontanelle, formed by the parietal and occipital bones, is small at birth and closes by 6 to 8 weeks of age, sometimes being closed already at birth. This contrasts with the anterior fontanelle, which remains open until 9 to 18 months. D widely open posterior fontanelle beyond 2 months suggests raised intracranial pressure, hydrocephalus, or congenital hypothyroidism.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.