E28.2: Polycystic ovarian syndrome

Yes. E28.2 is a valid four character ICD-10-CM code and may be reported on a claim. Its parent E28 is a category header and cannot be reported.

E28.1, androgen excess, records raised androgen output as an isolated finding. The tabular lists hypersecretion of ovarian androgens as its inclusion term. E28.2 records the syndrome, which rests on two of three clinical features rather than on one hormonal result. Where the note documents hirsutism with a raised testosterone and states no diagnosis of the syndrome, E28.1 is the code. E28.1 also carries a Use additional instruction for the adverse effect code identifying a drug, which E28.2 does not.

No. E28.2 does not map to a payment HCC under the CMS-HCC v28 model. The endocrine categories in v28 run to HCC 35 for pancreas transplant status, HCC 36, HCC 37 and HCC 38 for diabetes, HCC 48 for morbid obesity, and HCC 49, HCC 50 and HCC 51 for specified metabolic and endocrine disorders. Ovarian dysfunction appears in none of them. The comorbidities documented alongside PCOS are where risk adjustment sits, through E11.9 to HCC 38 and through the morbid obesity codes to HCC 48.

A polycystic ovary on ultrasound does not support E28.2 on its own. A polycystic appearance of the ovary is one of three diagnostic features. The 2023 International Evidence-based Guideline requires two of the three in an adult. That guideline also states that an ovarian ultrasound is not necessary for the diagnosis where irregular cycles and hyperandrogenism are both present. A radiology impression of polycystic appearing ovaries is not a diagnosis of the syndrome. E28.2 follows the provider's documented diagnosis. Section IV.D of the FY2027 ICD-10-CM Official Guidelines allows outpatient codes for signs and symptoms when the provider has not established a diagnosis. Where the provider has made no diagnosis, code the reason for the encounter and query.

Amenorrhea and oligomenorrhea are not coded alongside E28.2 where the menstrual disturbance is the syndrome. Category N91, absent, scanty and rare menstruation, carries an Excludes1 note for ovarian dysfunction (the E28 codes). An Excludes1 note means the two codes are not reported together for the same condition. Guideline I.A.12.a permits both only where the two conditions are unrelated to each other. The oligomenorrhea of PCOS is the ovarian dysfunction. E28.2 therefore stands alone. Assign N91.1 or N91.4 where secondary amenorrhea or secondary oligomenorrhea is documented and ovarian dysfunction is not the stated cause.

Both codes may be reported. Category N97 carries an Excludes2 note for female infertility associated with Stein-Leventhal syndrome (E28.2). An Excludes2 note permits the two codes together where the patient carries both conditions. Where the provider documents anovulatory infertility, assign N97.0 with E28.2. The alphabetic index also offers a single code path, routing Infertility, female, associated with Stein-Leventhal syndrome to E28.2. Sequencing follows Section IV.G of the FY2027 ICD-10-CM Official Guidelines, which puts N97.0 first at an infertility visit.

E28.2 carries no Code first instruction. No tabular note fixes its position. In the outpatient setting Section IV.G sequences the diagnosis chiefly responsible for the encounter first. That puts E28.2 first at a visit for the syndrome and second at a visit for a companion problem. On the inpatient side E28.2 reaches MDC 13 as a principal diagnosis and groups to MS-DRG 760 with CC or MCC, or MS-DRG 761 without. Section II.H allows an uncertain diagnosis documented at discharge to be coded as though established. That allowance does not extend to the outpatient setting.

E28.2 is unchanged in the FY2027 update, effective 1 October 2026. The FY2027 codes and tabular addenda make no addition, deletion or revision in category E28. The E28.2 descriptor and both inclusion terms are unchanged. Category E28 gained no codes and lost none in the FY2026 update, effective 1 October 2025.