O35.09X0
Maternal care for (suspected) other central nervous system malformation or damage in fetus, not applicable or unspecified
O35.09X0 (also written O3509X0) is a billable ICD-10-CM diagnosis code for maternal care for (suspected) other central nervous system malformation or damage in fetus, not applicable or unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 231 codes in category O35 (Maternal care for known or suspected fetal abnormality and damage). The Alphabetic Index lists it under 2 entries. Its 7th character, 0, means not applicable or unspecified. Its coding notes include a Use additional code instruction, a Code also instruction, 2 Excludes1 entries and 5 Excludes2 entries.
7th character
Category O35 requires a 7th character. O35.09 has only 5 characters, so a placeholder X fills the 6th position.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
The trimester character comes from the provider's documentation for the current encounter. The unspecified trimester code should rarely be used.
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (1 note)
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
- any associated maternal condition
Excludes1
Not coded here. The listed conditions generally should not be reported together.
- encounter for suspected maternal and fetal conditions ruled out (Z03.7-)
Also from chapter/block level (1 note)
- supervision of normal pregnancy (Z34.-)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
- chromosomal abnormality in fetus (O35.1-)
Also from chapter/block level (4 notes)
Includes
Further defines or gives examples of the content of the category.
- the listed conditions in the fetus as a reason for hospitalization or other obstetric care to the mother, or for termination of pregnancy
Notes
Also from chapter/block level (6 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
Alphabetic Index terms
Terms the official Alphabetic Index lists for O35.09. This code adds the 7th character. 2 entries
- Pregnancy (single) (uterine), complicated by (care of) (management affected by), fetal (maternal care for), central nervous system malformation or damage, specified type NEC
- Pregnancy (single) (uterine), complicated by (care of) (management affected by), malformation, central nervous system, specified type NEC