ICD-10-CM > O00-O9A > O85-O92 > O91 > O91.1 > O91.11 O91.11 Abscess of breast associated with pregnancy Non-Billable/Non-Specific Applicable To Gestational mammary abscessGestational purulent mastitisGestational subareolar abscess Codes O91.111Abscess of breast associated with pregnancy, first trimesterO91.112Abscess of breast associated with pregnancy, second trimesterO91.113Abscess of breast associated with pregnancy, third trimesterO91.119Abscess of breast associated with pregnancy, unspecified trimester