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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Microcephaly is defined as head circumference _________
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The correct answer is  *Microcephaly is defined as an occipitofrontal circumference more than 3 standard detions (SD) below the mean for given age, sex and gestation. *Causes are structural brain malformations, inherited syndromes, congenital or acquired infections, hypoxic ischemic insults and rarely metabolic disorders. Isolated inherited microcephaly is autosomal recessive. Reference : page 36 Ghai Essential Pediatrics 9 th edition