ICD-10-CM > O00-O9A > O20-O29 > O24 > O24.4 > O24.42 O24.42 Gestational diabetes mellitus in childbirth Non-Billable/Non-Specific Codes O24.420Gestational diabetes mellitus in childbirth, diet controlledO24.424Gestational diabetes mellitus in childbirth, insulin controlledO24.425Gestational diabetes mellitus in childbirth, controlled by oral hypoglycemic drugsO24.429Gestational diabetes mellitus in childbirth, unspecified control