Coding and coverage · ICD-10-CM

O35 Maternal care for known or suspected fetal abnormality and damage

Not billable (header)Chapter 15

This code needs a 7th character (use X as a placeholder for missing characters).

Check coverage with this diagnosis

Codes under this one

  • O35.0 Maternal care for (suspected) central nervous system malformation in fetusHeader
  • O35.1 Maternal care for (suspected) chromosomal abnormality in fetusHeader
  • O35.2 Maternal care for (suspected) hereditary disease in fetusHeader
  • O35.3 Maternal care for (suspected) damage to fetus from viral disease in motherHeader
  • O35.4 Maternal care for (suspected) damage to fetus from alcoholHeader
  • O35.5 Maternal care for (suspected) damage to fetus by drugsHeader
  • O35.6 Maternal care for (suspected) damage to fetus by radiationHeader
  • O35.7 Maternal care for (suspected) damage to fetus by other medical proceduresHeader
  • O35.8 Maternal care for other (suspected) fetal abnormality and damageHeader
  • O35.9 Maternal care for (suspected) fetal abnormality and damage, unspecifiedHeader
  • O35.A Maternal care for other (suspected) fetal abnormality and damage, fetal facial anomaliesHeader
  • O35.B Maternal care for other (suspected) fetal abnormality and damage, fetal cardiac anomaliesHeader
  • O35.C Maternal care for other (suspected) fetal abnormality and damage, fetal pulmonary anomaliesHeader
  • O35.D Maternal care for other (suspected) fetal abnormality and damage, fetal gastrointestinal anomaliesHeader
  • O35.E Maternal care for other (suspected) fetal abnormality and damage, fetal genitourinary anomaliesHeader
  • O35.F Maternal care for other (suspected) fetal abnormality and damage, fetal musculoskeletal anomalies of trunkHeader
  • O35.G Maternal care for other (suspected) fetal abnormality and damage, fetal upper extremities anomaliesHeader
  • O35.H Maternal care for other (suspected) fetal abnormality and damage, fetal lower extremities anomaliesHeader

Instructional notes

Chapter 15

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • supervision of normal pregnancy (Z34.-)
Excludes2Not included here: the patient may have both; report both when both are present.
  • mental and behavioral disorders associated with the puerperium (F53.-)
  • obstetrical tetanus (A34)
  • postpartum necrosis of pituitary gland (E23.0)
  • puerperal osteomalacia (M83.0)
Use additional codeAdd a second code for the full picture.
  • code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Notes
  • CODES FROM THIS CHAPTER ARE FOR USE ONLY ON MATERNAL RECORDS, NEVER ON NEWBORN RECORDS
  • Codes from this chapter are for use for conditions related to or aggravated by the pregnancy, childbirth, or by the puerperium (maternal causes or obstetric causes)
  • Trimesters are counted from the first day of the last menstrual period. They are defined as follows:
  • 1st trimester- less than 14 weeks 0 days
  • 2nd trimester- 14 weeks 0 days to less than 28 weeks 0 days
  • 3rd trimester- 28 weeks 0 days until delivery

This code

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • encounter for suspected maternal and fetal conditions ruled out (Z03.7-)
Code also
  • any associated maternal condition
Includes
  • the listed conditions in the fetus as a reason for hospitalization or other obstetric care to the mother, or for termination of pregnancy
7th charactersOne 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

Chapter 15: Pregnancy, childbirth and the puerperium (O00-O9A) · O30-O48 Maternal care related to the fetus and amniotic cavity and possible delivery problems (O30-O48)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.