O99.281 Endocrine, nutritional and metabolic diseases complicating pregnancy, first trimester

Billable ICD-10-CM code, FY2026.

Applies from O99 Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

Includes

• conditions which complicate the pregnant state, are aggravated by the pregnancy or are a main reason for obstetric care

Excludes2 (not included here)

• when the reason for maternal care is that the condition is known or suspected to have affected the fetus (O35-O36)

Use additional code

• code to identify specific condition

Applies from O99.2 Endocrine, nutritional and metabolic diseases complicating pregnancy, childbirth and the puerperium

Applicable to

• Conditions in E00-E89

Excludes2 (not included here)

• diabetes mellitus (O24.-)
• malnutrition (O25.-)
• postpartum thyroiditis (O90.5)

MS-DRG index

Defines the logic of DRG(s) 817-819 in MDC 14.

Approximate ICD-9-CM (GEMs)

• 648.91 Other current conditions classifiable elsewhere of mother, delivered, with or without mention of antepartum condition (approximate)
• 648.93 Other current conditions classifiable elsewhere of mother, antepartum condition or complication (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Maternity diagnoses (age 9 through 64): Age conflict edit. These diagnoses are clinically expected only in patients age 9 through 64.

Nearby codes

• O99.213 Obesity complicating pregnancy, third trimester
• O99.214 Obesity complicating childbirth
• O99.215 Obesity complicating the puerperium
• O99.28 Other endocrine, nutritional and metabolic diseases complicating pregnancy, childbirth and the puerperium
• O99.280 Endocrine, nutritional and metabolic diseases complicating pregnancy, unspecified trimester
• O99.281 Endocrine, nutritional and metabolic diseases complicating pregnancy, first trimester (this code)
• O99.282 Endocrine, nutritional and metabolic diseases complicating pregnancy, second trimester
• O99.283 Endocrine, nutritional and metabolic diseases complicating pregnancy, third trimester
• O99.284 Endocrine, nutritional and metabolic diseases complicating childbirth
• O99.285 Endocrine, nutritional and metabolic diseases complicating the puerperium
• O99.3 Mental disorders and diseases of the nervous system complicating pregnancy, childbirth and the puerperium