ICD-10-CM 2027 diagnosis code
O66Other obstructed labor
O66 is a header code, so it can't be reported by itself. Choose one of the 9 more specific codes beneath it.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About O66
O66 is the ICD-10-CM diagnosis code for other obstructed labor. It belongs to block O60-O77 (complications of labor and delivery) and chapter 15 (pregnancy, childbirth and the puerperium). It is a header code, so it can't be reported by itself; one of its 9 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: O66.0 (dystocia), O66.1 (twins), O66.2 (fetus), O66.3 (fetus), O66.4 (labor), O66.5 (forceps), O66.6 (fetuses), O66.8 (labor) and 1 more.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under O66
- O66.0Obstructed labor due to shoulder dystociaBillable
- O66.1Obstructed labor due to locked twinsBillable
- O66.2Obstructed labor due to unusually large fetusBillable
- O66.3Obstructed labor due to other abnormalities of fetusBillable
- O66.4Failed trial of labor
- O66.5Attempted application of vacuum extractor and forcepsBillable
- O66.6Obstructed labor due to other multiple fetusesBillable
- O66.8Other specified obstructed laborBillable
- O66.9Obstructed labor, unspecifiedBillable
Notes that apply from higher levels
Instructions written at a parent level also apply to O66.
Broader instructions also apply from Chapter 15: Pregnancy, childbirth and the puerperium.
Codes whose notes reference O66
- O33Excludes1
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about O66
Is O66 billable?
- No. O66 is a header code. Report one of its more specific subcodes instead.