When does the posterior fontanel typically close?

When does the posterior fontanel typically close?

• A. At birth
• B. By the 2nd month
• C. By the 4th month
• D. By the 6th month

Answer: (C)

The posterior fontanel, which is one of the soft spots on a newborn's skull, typically closes by the fourth month of life. At birth, infants usually have both anterior and posterior fontanels to allow for the skull to flex during delivery and provide space for the rapidly growing brain. The closure of the posterior fontanel usually occurs within the range of 6 to 8 weeks after birth, with most sources indicating that it should be closed by the end of the fourth month. This is a crucial milestone in development as it reflects the ongoing growth and development of the infant's brain and skull. In infancy, monitoring the timing of fontanel closure helps healthcare providers ensure that the child's growth is progressing normally. If the closure occurs significantly later than expected, it could indicate potential developmental issues that require further assessment.

The posterior fontanel, which is one of the soft spots on a newborn's skull, typically closes by the fourth month of life. At birth, infants usually have both anterior and posterior fontanels to allow for the skull to flex during delivery and provide space for the rapidly growing brain. The closure of the posterior fontanel usually occurs within the range of 6 to 8 weeks after birth, with most sources indicating that it should be closed by the end of the fourth month. This is a crucial milestone in development as it reflects the ongoing growth and development of the infant's brain and skull.

In infancy, monitoring the timing of fontanel closure helps healthcare providers ensure that the child's growth is progressing normally. If the closure occurs significantly later than expected, it could indicate potential developmental issues that require further assessment.