Pediatrics Microcephaly is defined as a: A Head circumference more than 2 SD above the mean for age and sex B Head circumference more than 3SD above the mean for age and sex C Head circumference more than 10th percentile above the mean for age and sex D Head circumference more than 15th percentile above the mean for age and sex 💡 Explanation Microcephaly is defined as a: ✓ Correct Answer: A. Head circumference more than 2 SD above the mean for age and sex