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ICD-10/O35.11X2

O35.11X2 ICD-10-CM Code: Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 2

O35.11X2 is the authoritative medical code for Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 2. This classification is used in medical billing and clinical recording to specify the clinical criteria for maternal care for (suspected) chromosomal abnormality in fetus, trisomy 13, fetus 2 (ICD-10-CM O35.11X2), ensuring healthcare documentation aligns with current federal coding standards.

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Inpatient Payment Groups (MS-DRG)

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0 (FY2026), Appendix B.

  • MS-DRG 817 — OTHER ANTEPARTUM DIAGNOSES WITH O.R. PROCEDURES WITH MCC (MDC 14)
  • MS-DRG 818 — OTHER ANTEPARTUM DIAGNOSES WITH O.R. PROCEDURES WITH CC (MDC 14)
  • MS-DRG 819 — OTHER ANTEPARTUM DIAGNOSES WITH O.R. PROCEDURES WITHOUT CC/MCC (MDC 14)
  • MS-DRG 831 — OTHER ANTEPARTUM DIAGNOSES WITHOUT O.R. PROCEDURES WITH MCC (MDC 14)
  • MS-DRG 832 — OTHER ANTEPARTUM DIAGNOSES WITHOUT O.R. PROCEDURES WITH CC (MDC 14)
  • MS-DRG 833 — OTHER ANTEPARTUM DIAGNOSES WITHOUT O.R. PROCEDURES WITHOUT CC/MCC (MDC 14)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Code Set: Valid FY2026 and FY2027. FY2026 took effect October 1, 2025.

Official Registry Overview & Definition

Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 2 is a billable ICD-10-CM diagnosis code (O35.112). Includes: the listed conditions in the fetus as a reason for hospitalization or other obstetric care to the mother, or for termination of pregnancy. Excludes1 (not coded here): encounter for suspected maternal and fetal conditions ruled out (Z03.7-). Code also: any associated maternal condition. 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..

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for O35.11X2 in the official ICD-10-CM tabular list.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

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

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Maternal care for (suspected) chromosomal abnormality in fetus, Patau syndrome

Excludes1 — Not Coded Here

Conditions that can never be reported with this code; the two are mutually exclusive.

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

Code Also

Additional codes that may be required to fully describe the encounter.

  • any associated maternal condition

Frequently Asked Questions (FAQ) & Clinical Guidance

Does O35.11X2 require a 7th character?

Yes. 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..

What can't be coded together with O35.11X2?

Per official ICD-10-CM Excludes1 instructions, O35.11X2 must not be reported together with: encounter for suspected maternal and fetal conditions ruled out (Z03.7-).

What conditions are included under O35.11X2?

Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 2 includes: Maternal care for (suspected) chromosomal abnormality in fetus, Patau syndrome.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to O35.11X2 in its code family, with their registry titles.

  • O35.10X5 — Maternal care for (suspected) chromosomal abnormality in fetus, unspecified, fetus 5
  • O35.10X9 — Maternal care for (suspected) chromosomal abnormality in fetus, unspecified, other fetus
  • O35.11 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13
  • O35.11X0 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, not applicable or unspecified
  • O35.11X1 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 1
  • O35.11X3 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 3
  • O35.11X4 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 4
  • O35.11X5 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, fetus 5
  • O35.11X9 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 13, other fetus
  • O35.12 — Maternal care for (suspected) chromosomal abnormality in fetus, Trisomy 18

View all codes in the O35 family