MCMedicalCodingSoftware
O35

O35: Maternal care for known or suspected fetal abnormality and damage

Non-billable headerICD-10-CM

O35 is a non-billable header ICD-10-CM code for maternal care for known or suspected fetal abnormality and damage. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

One of the following 7th characters is to be assigned to each code under category O35. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning a code from category O35 that has a 7th character of 1 through 9.

0
not applicable or unspecified
1
fetus 1
2
fetus 2
3
fetus 3
4
fetus 4
5
fetus 5
9
other fetus

Excludes1: never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • encounter for suspected maternal and fetal conditions ruled out (Z03.7-)

Code also

Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.

  • any associated maternal condition

Includes

Conditions this code covers.

  • the listed conditions in the fetus as a reason for hospitalization or other obstetric care to the mother, or for termination of pregnancy

Other codes that can never be billed with O35

Their own Excludes1 notes name this code, so the conflict is not listed above.

  • Z03.7Encounter for suspected maternal and fetal conditions ruled out
  • O09.829Supervision of pregnancy with history of in utero procedure during previous pregnancy, unspecified trimester

Risk adjustment

No CMS-HCC V28 category: this code does not change a RAF score.

Code history

Unchanged in every release from FY2024 to FY2027.

Code to one of these instead O35

18 child codes. Green means billable.

ICD-10-CMFY2027· effective October 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release: see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.