TY - CHAP M1 - Book, Section TI - Macrocephaly A1 - Bianchi, Diana W. A1 - Crombleholme, Timothy M. A1 - D'Alton, Mary E. A1 - Malone, Fergal D. PY - 2015 T2 - Fetology: Diagnosis and Management of the Fetal Patient, 2e AB - Key PointsMacrocephaly is defined as a head circumference greater than three standard deviations (SDs) above the mean for age and sex.This disorder is rare, and the exact incidence is unknown.The antenatal natural history has not been elucidated.During the antepartum period, other causes of macrocephaly should be excluded such as hydrocephalus or intracranial space-occupying lesion.The diagnosis of macrocephaly should not alter prenatal care with regard to timing of delivery or mode of delivery.Long-term outcome regarding macrocephaly is sparse. The majority of cases appear to do well; however, it appears to be associated with an increased risk for autism. Unilateral macrocephaly seems to be associated with poor outcomes.The inheritance pattern of benign macrocephaly is autosomal dominant with incomplete penetrance with a male to female preponderance of 4:1. Differential diagnosis should include consideration of overgrowth syndromes, which may be due to single-gene disorders. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - obgyn.mhmedical.com/content.aspx?aid=1106396627 ER -