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

Not billable

Is O99 billable?

No — O99 is a non-billable header code. O99 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 60 billable codes beneath O99.

Billable codes under this header

O99 at a glance

Code	O99
Description	Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium
Billable	No — header code
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Use additional code

Report an additional code alongside O99 to fully describe the condition. O99 is sequenced first.

code to identify specific condition

Excludes2 — not included here

The conditions below are not part of O99, but a patient may have both at the same time. When documentation supports it, O99 and the excluded code may both be reported.

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

Includes

Conditions classified to O99.

conditions which complicate the pregnant state, are aggravated by the pregnancy or are a main reason for obstetric care

Excludes1 — never code together — inherited from Chapter 15

The conditions below can never be reported together with O99 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

supervision of normal pregnancy (Z34.-)

Use additional code — inherited from Chapter 15

Report an additional code alongside O99 to fully describe the condition. O99 is sequenced first.

code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.

Excludes2 — not included here — inherited from Chapter 15

The conditions below are not part of O99, but a patient may have both at the same time. When documentation supports it, O99 and the excluded code may both be reported.

mental and behavioral disorders associated with the puerperium (F53.-)
obstetrical tetanus (A34)
postpartum necrosis of pituitary gland (E23.0)
puerperal osteomalacia (M83.0)

What codes fall under O99? (9)

How long has O99 existed?

O99 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.

Which codes are confused with O99?

ICD-10-CM declares these codes mutually exclusive with O99 — exactly one of each pair can be correct for a given encounter.