DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

O33 Maternal care for disproportion

  • Header · not billable
  • Some codes take a 7th character

O33 is not billable. The category heads 40 billable codes in FY2027, grouped under 10 subdivisions.

Index → code

  • Android pelviswith disproportion (fetopelvic) → O33.3
  • Nägele's pelviswith disproportion (fetopelvic) → O33.0
  • Robert's pelviswith disproportion (fetopelvic) → O33.0

Where it sits

  1. Chapter 15 Pregnancy, childbirth and the puerperium (O00-O9A)
  2. O30-O48 Maternal care related to the fetus and amniotic cavity and possible delivery problems (O30-O48)
  3. O33 Maternal care for disproportion
Billable codes
40
Subdivisions
10
CC / MCC codes
1 / 0
HCC V28 codes
0
New FY2027
0
Index entries
50

Codes in O33

  1. O33.0
    Maternal care for disproportion due to deformity of maternal pelvic bones
    BillableCC
    Inclusion terms 1

    Inclusion terms

    • Maternal care for disproportion due to pelvic deformity causing disproportion NOS
  2. O33.1
    Maternal care for disproportion due to generally contracted pelvis
    Billable
    Inclusion terms 1

    Inclusion terms

    • Maternal care for disproportion due to contracted pelvis NOS causing disproportion
  3. O33.2
    Maternal care for disproportion due to inlet contraction of pelvis
    Billable
    Inclusion terms 1

    Inclusion terms

    • Maternal care for disproportion due to inlet contraction (pelvis) causing disproportion
  4. O33.3
    Maternal care for disproportion due to outlet contraction of pelvis +7th: 0 1 2 3 4 5 9
    Needs 7th character
    Inclusion terms 2

    Inclusion terms

    • Maternal care for disproportion due to mid-cavity contraction (pelvis)
    • Maternal care for disproportion due to outlet contraction (pelvis)
  5. O33.4
    Maternal care for disproportion of mixed maternal and fetal origin +7th: 0 1 2 3 4 5 9
    Needs 7th character
  6. O33.5
    Maternal care for disproportion due to unusually large fetus +7th: 0 1 2 3 4 5 9
    Needs 7th character
    Inclusion terms 2

    Inclusion terms

    • Maternal care for disproportion due to disproportion of fetal origin with normally formed fetus
    • Maternal care for disproportion due to fetal disproportion NOS
  7. O33.6
    Maternal care for disproportion due to hydrocephalic fetus +7th: 0 1 2 3 4 5 9
    Needs 7th character
  8. O33.7
    Maternal care for disproportion due to other fetal deformities +7th: 0 1 2 3 4 5 9
    Needs 7th character
    Inclusion terms 5, Excludes1 1

    Inclusion terms

    • Maternal care for disproportion due to fetal ascites
    • Maternal care for disproportion due to fetal hydrops
    • Maternal care for disproportion due to fetal meningomyelocele
    • Maternal care for disproportion due to fetal sacral teratoma
    • Maternal care for disproportion due to fetal tumor

    Excludes1

    • obstructed labor due to other fetal deformities (O66.3) O66.3
  9. O33.8
    Maternal care for disproportion of other origin
    Billable
  10. O33.9
    Maternal care for disproportion, unspecified
    Billable
    Inclusion terms 2

    Inclusion terms

    • Maternal care for disproportion due to cephalopelvic disproportion NOS
    • Maternal care for disproportion due to fetopelvic disproportion NOS

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column. Rows marked +7th need a 7th character: pick one to build the full code; its code card has its own flags.

Instructions

At O33

Includes

  • the listed conditions as a reason for observation, hospitalization or other obstetric care of the mother, or for cesarean delivery before onset of labor

Excludes1

  • disproportion with obstructed labor (O65-O66) O65 O66

Notes that also apply

Chapter 15 instructions (Notes 6, Excludes1 1, Excludes2 4, Use additional code 1): printed on the chapter 15 page.

7th characters

7th characters for O33.3 defined at O33.3

One of the following 7th characters is to be assigned to code O33.3. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning code O33.3 with a 7th character of 1 through 9.

7th characters for O33.3
7thMeaning (NCHS)
0not applicable or unspecified
1fetus 1
2fetus 2
3fetus 3
4fetus 4
5fetus 5
9other fetus

7th characters for O33.4 defined at O33.4

One of the following 7th characters is to be assigned to code O33.4. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning code O33.4 with a 7th character of 1 through 9.

7th characters for O33.4
7thMeaning (NCHS)
0not applicable or unspecified
1fetus 1
2fetus 2
3fetus 3
4fetus 4
5fetus 5
9other fetus

7th characters for O33.5 defined at O33.5

One of the following 7th characters is to be assigned to code O33.5. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning code O33.5 with a 7th character of 1 through 9.

7th characters for O33.5
7thMeaning (NCHS)
0not applicable or unspecified
1fetus 1
2fetus 2
3fetus 3
4fetus 4
5fetus 5
9other fetus

7th characters for O33.6 defined at O33.6

One of the following 7th characters is to be assigned to code O33.6. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning code O33.6 with a 7th character of 1 through 9.

7th characters for O33.6
7thMeaning (NCHS)
0not applicable or unspecified
1fetus 1
2fetus 2
3fetus 3
4fetus 4
5fetus 5
9other fetus

7th characters for O33.7 defined at O33.7

One of the following 7th characters is to be assigned to code O33.7. 7th character 0 is for single gestations and multiple gestations where the fetus is unspecified. 7th characters 1 through 9 are for cases of multiple gestations to identify the fetus for which the code applies. The appropriate code from category O30, Multiple gestation, must also be assigned when assigning code O33.7 with a 7th character of 1 through 9.

7th characters for O33.7
7thMeaning (NCHS)
0not applicable or unspecified
1fetus 1
2fetus 2
3fetus 3
4fetus 4
5fetus 5
9other fetus

A code that takes a 7th character is invalid without it; the placeholder X fills a code shorter than 6 characters (Official Guidelines I.A.5). How 7th characters work.

Index entries

  • Anthropoid pelviswith disproportion (fetopelvic) → O33.0
  • Nägele's pelviswith disproportion (fetopelvic) → O33.0
  • Pithecoid pelviswith disproportion (fetopelvic) → O33.0
  • Platypelloid pelviswith disproportion (fetopelvic) → O33.0
  • Prominence, prominentischial spine or sacral promontory with disproportion (fetopelvic) → O33.0
  • Robert's pelviswith disproportion (fetopelvic) → O33.0
  • Scoliotic pelviswith disproportion (fetopelvic) → O33.0
  • Spondylolisthesis (acquired) (degenerative)with disproportion (fetopelvic) → O33.0
  • Android pelviswith disproportion (fetopelvic) → O33.3
  • Male type pelviswith disproportion (fetopelvic) → O33.3
  • Hydrocephalus (acquired) (external) (internal) (malignant) (recurrent)causing disproportion → O33.6
  • Cretin, cretinism (congenital) (endemic) (nongoitrous) (sporadic)pelviswith disproportion (fetopelvic) → O33.0
  • Deformitypelvis, pelvic (acquired) (bony)with disproportion (fetopelvic) → O33.0
  • Flatpelviswith disproportion (fetopelvic) → O33.0
  • Rachiticpelvis (late effect) (sequelae)with disproportion (fetopelvic) → O33.0
  • Spondylolysis (acquired)lumbosacral regionwith disproportion (fetopelvic) → O33.0
  • Spondylosiswithdisproportion (fetopelvic) → O33.0
  • Tippingpelviswith disproportion (fetopelvic) → O33.0
  • Contraction(s), contracture, contractedpelvis (acquired) (general)with disproportion (fetopelvic) → O33.1
  • Infancy, infantile, infantilismpelviswith disproportion (fetopelvic) → O33.1
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)contracted pelvis (general) → O33.1
  • Small (ness)pelviswith disproportion (fetopelvic) → O33.1
  • Funnelpelvis (acquired)with disproportion (fetopelvic) → O33.3
  • Delivery (childbirth) (labor)cesarean (for)increased size, fetus → O33.5
  • Delivery (childbirth) (labor)cesarean (for)oversize fetus → O33.5
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)oversize fetus → O33.5
  • Delivery (childbirth) (labor)cesarean (for)hydrocephalic fetus → O33.6
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)hydrocephalic fetus (disproportion) → O33.6
  • Deformityfetalwith fetopelvic disproportion → O33.7
  • Distortion(s) (congenital)lumbar spinewith disproportion → O33.8
  • Delivery (childbirth) (labor)cesarean (for)cephalopelvic disproportion → O33.9
  • Delivery (childbirth) (labor)cesarean (for)disproportion NOS → O33.9
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)disproportion (due to) → O33.9
  • Delivery (childbirth) (labor)cesarean (for)abnormalpelvis (bony) (deformity) (major) NEC with disproportion (fetopelvic) → O33.0
  • Delivery (childbirth) (labor)cesarean (for)deformity (acquired) (congenital)pelvis (bony) NEC → O33.0
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)abnormal, abnormalitypelvis (bony) (major) NEC → O33.0
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)disproportion (due to)generally contracted pelvis → O33.1
  • Contraction(s), contracture, contractedpelvis (acquired) (general)with disproportion (fetopelvic)inlet → O33.2
  • Delivery (childbirth) (labor)cesarean (for)contracted pelvis (general)inlet → O33.2
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)contracted pelvis (general)inlet → O33.2

10 more, longer entries are not listed; the search box finds them by word.

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy