ICD-10-CM > O00-O9A > O85-O92 > O91 > O91.0 > O91.01 O91.01 Infection of nipple associated with pregnancy Non-Billable/Non-Specific Applicable To Gestational abscess of nipple Codes O91.011Infection of nipple associated with pregnancy, first trimesterO91.012Infection of nipple associated with pregnancy, second trimesterO91.013Infection of nipple associated with pregnancy, third trimesterO91.019Infection of nipple associated with pregnancy, unspecified trimester