ICD-10-CM 2027
ICD-10 code for XY mosaicism
From the official ICD-10-CM alphabetic index entry “Mosaicism, mosaic (autosomal) (chromosomal) › XY”. Page updated September 29, 2026.
About coding XY mosaicism
The ICD-10-CM code for XY mosaicism is Q96.3 (Mosaicism, 45, X/46, XX or XY).
Within Q96 (Turner's syndrome), Q96.3 is specifically for mosaicism, 45, X/46, XX or XY. Related codes cover karyotype 45, X (Q96.0), karyotype 46, X iso (Xq) (Q96.1), karyotype 46, X with abnormal sex chromosome, except iso (Xq) (Q96.2), mosaicism, 45, X/other cell line(s) with abnormal sex chromosome (Q96.4), other variants of Turner's syndrome (Q96.8) and unspecified (Q96.9).
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 742 (Uterine and Adnexa Procedures for Non-Malignancy with CC/MCC, relative weight 1.8456), DRG 743 (Uterine and Adnexa Procedures for Non-Malignancy without CC/MCC, relative weight 1.2974), DRG 760 (Menstrual and Other Female Reproductive System Disorders with CC/MCC, relative weight 1.0129) and DRG 761 (Menstrual and Other Female Reproductive System Disorders without CC/MCC, relative weight 0.7041), in MDC 13 (Diseases and Disorders of the Female Reproductive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about XY mosaicism ICD-10 codes
What is the ICD-10 code for XY mosaicism?
- Q96.3 — Mosaicism, 45, X/46, XX or XY.
Is Q96.3 billable?
- Yes. Q96.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Q96.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict Q96.3 as a principal diagnosis.
Is Q96.3 a CC or MCC?
- No. Q96.3 is neither a CC nor an MCC under MS-DRG v44.0.