O09.899Supervision of other high risk pregnancies, unspecified trimester

O09.899 is the ICD-10-CM diagnosis code for supervision of other high risk pregnancies, unspecified trimester. It belongs to category O09 (supervision of high risk pregnancy), block O09 (supervision of high risk pregnancy) and chapter 15 (pregnancy, childbirth and the puerperium). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within O09.89, choose O09.899 (unspecified trimester) only when documentation doesn't support a more specific option: first trimester (O09.891), second trimester (O09.892) and third trimester (O09.893).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 998 (Principal Diagnosis Invalid as Discharge Diagnosis), in MDC 14 (Pregnancy, Childbirth and the Puerperium), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

The Medicare Code Editor treats this as a maternity diagnosis, expected only for patients age 9 through 64.

It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.

It is on the CMS list of diagnoses consistent only with female patients (the sex-conflict edit itself was retired in FY2025).

It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as V23.89 (supervision of other high-risk pregnancy).