ICD-10-CM 2027 diagnosis code
O33Maternal care for disproportion
O33 is a header code, so it can't be reported by itself. Choose one of the 10 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 O33
O33 is the ICD-10-CM diagnosis code for maternal care for disproportion. It belongs to block O30-O48 (maternal care related to the fetus and amniotic cavity and possible delivery problems) and chapter 15 (pregnancy, childbirth and the puerperium). It is a header code, so it can't be reported by itself; one of its 10 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: O33.0 (due to deformity of maternal pelvic bones), O33.1 (due to generally contracted pelvis), O33.2 (due to inlet contraction of pelvis), O33.3 (due to outlet contraction of pelvis), O33.4 (of mixed maternal and fetal origin), O33.5 (due to unusually large fetus), O33.6 (due to hydrocephalic fetus), O33.7 (due to other fetal deformities) and 2 more.
Don't report O33 together with the conditions in its Excludes1 note: disproportion with obstructed labor (O65-O66).
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 O33
- O33.0Maternal care for disproportion due to deformity of maternal pelvic bonesBillable
- O33.1Maternal care for disproportion due to generally contracted pelvisBillable
- O33.2Maternal care for disproportion due to inlet contraction of pelvisBillable
- O33.3Maternal care for disproportion due to outlet contraction of pelvis
- O33.4Maternal care for disproportion of mixed maternal and fetal origin
- O33.5Maternal care for disproportion due to unusually large fetus
- O33.6Maternal care for disproportion due to hydrocephalic fetus
- O33.7Maternal care for disproportion due to other fetal deformities
- O33.8Maternal care for disproportion of other originBillable
- O33.9Maternal care for disproportion, unspecifiedBillable
Coding notes
- the listed conditions as a reason for observation, hospitalization or other obstetric care of the mother, or for cesarean delivery before onset of labor
Notes that apply from higher levels
Instructions written at a parent level also apply to O33.
Broader instructions also apply from Chapter 15: Pregnancy, childbirth and the puerperium.
Codes whose notes reference O33
- M95.5Excludes1
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 O33
Is O33 billable?
- No. O33 is a header code. Report one of its more specific subcodes instead.