766 Disorders relating to long gestation and high birthweight 
766.0 Exceptionally large baby relating to long gestation convert 766.0 to ICD-10-CM 766.1 Other 'heavy-for-dates' infants not related to gestation period convert 766.1 to ICD-10-CM
766.2 "late infant, not 'heavy-for-dates'" 
766.21 Post-term infant convert 766.21 to ICD-10-CM 766.22 Prolonged gestation of infant convert 766.22 to ICD-10-CM