Is O99.42 a billable ICD-10-CM code?

Yes. O99.42 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does O99.42 sit in the tabular list?

Pregnancy, childbirth and the puerperium (O00-O9A), in the block Other obstetric conditions, not elsewhere classified (O94-O9A).

What cannot be coded together with O99.42?

O99.42 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above O99.42 (O99.4) and apply to it just the same.

O99.42

O99.42 — Diseases of the circulatory system complicating childbirth

Billable / specific codeICD-10-CM

O99.42 is a billable, specific ICD-10-CM code for diseases of the circulatory system complicating childbirth. It is valid for submission on a claim.

Excludes1 inherited from the categories above O99.42

These are not written on O99.42, but they bind it: a note on a category applies to every code beneath it. Billing O99.42 with anything listed here is a denial.

Written on O99.4 — Diseases of the circulatory system complicating pregnancy, childbirth and the puerperium

peripartum cardiomyopathy (O90.3)

Excludes2 inherited from the categories above O99.42

Also inherited, and the opposite of Excludes1: these conditions are not part of O99.42, but a patient can have both, so you may code both.

Written on O99.4 — Diseases of the circulatory system complicating pregnancy, childbirth and the puerperium

hypertensive disorders (O10-O16)
obstetric embolism (O88.-)
venous complications and cerebrovenous sinus thrombosis in labor, childbirth and the puerperium (O87.-)
venous complications and cerebrovenous sinus thrombosis in pregnancy (O22.-)

Written on O99 — Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

when the reason for maternal care is that the condition is known or suspected to have affected the fetus (O35-O36)

Risk adjustment

O99.42 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

O99.42 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A57326Billing and Coding: Electrocardiograms

How O99.42 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to O99.42.

Delivery›complicated›by›circulatory system disorder

Code history

O99.42 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share O99.4. If O99.42 is not quite right, the correct code is usually one of these.

Questions about O99.42

Is O99.42 a billable ICD-10-CM code?: Yes. O99.42 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does O99.42 sit in the tabular list?: Pregnancy, childbirth and the puerperium (O00-O9A), in the block Other obstetric conditions, not elsewhere classified (O94-O9A).
What cannot be coded together with O99.42?: O99.42 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above O99.42 (O99.4) and apply to it just the same.