DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

O31 Complications specific to multiple gestation

  • Header · not billable
  • Codes take a 7th character

O31 is not billable. The category heads 168 billable codes in FY2027, grouped under 6 subdivisions. Its codes take a 7th character, so none is complete with fewer than 7 characters.

FY2027 changes under O31: 28 billable codes added. All FY2027 changes.

Index → code

  • Papyraceous fetus → O31.0-
  • Fetus, fetalcompressus → O31.0-
  • Fetus, fetalpapyraceous → O31.0-

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. O31 Complications specific to multiple gestation
Billable codes
168
Subdivisions
6
CC / MCC codes
21 / 0
HCC V28 codes
0
New FY2027
28
Index entries
14

Codes in O31

  1. O31.0
    Papyraceous fetus
    Header
    Inclusion terms 1

    Inclusion terms

    • Fetus compressus
  2. O31.00
    Papyraceous fetus, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  3. O31.01
    Papyraceous fetus, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  4. O31.02
    Papyraceous fetus, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  5. O31.03
    Papyraceous fetus, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  6. O31.1
    Continuing pregnancy after spontaneous abortion of one fetus or more
    Header
  7. O31.10
    Continuing pregnancy after spontaneous abortion of one fetus or more, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  8. O31.11
    Continuing pregnancy after spontaneous abortion of one fetus or more, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  9. O31.12
    Continuing pregnancy after spontaneous abortion of one fetus or more, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  10. O31.13
    Continuing pregnancy after spontaneous abortion of one fetus or more, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  11. O31.2
    Continuing pregnancy after intrauterine death of one fetus or more
    Header
  12. O31.20
    Continuing pregnancy after intrauterine death of one fetus or more, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  13. O31.21
    Continuing pregnancy after intrauterine death of one fetus or more, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  14. O31.22
    Continuing pregnancy after intrauterine death of one fetus or more, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  15. O31.23
    Continuing pregnancy after intrauterine death of one fetus or more, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  16. O31.3
    Continuing pregnancy after elective fetal reduction of one fetus or more
    Header
    Inclusion terms 1

    Inclusion terms

    • Continuing pregnancy after selective termination of one fetus or more
  17. O31.30
    Continuing pregnancy after elective fetal reduction of one fetus or more, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  18. O31.31
    Continuing pregnancy after elective fetal reduction of one fetus or more, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  19. O31.32
    Continuing pregnancy after elective fetal reduction of one fetus or more, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  20. O31.33
    Continuing pregnancy after elective fetal reduction of one fetus or more, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  21. O31.4
    Continuing pregnancy after vanishing twin syndrome of one fetus or more New FY2027
    Header
  22. O31.40
    Continuing pregnancy after vanishing twin syndrome of one fetus or more, unspecified trimester New FY2027 +7th: 0 1 2 3 4 5 9
    Needs 7th character
  23. O31.41
    Continuing pregnancy after vanishing twin syndrome of one fetus or more, first trimester New FY2027 +7th: 0 1 2 3 4 5 9
    Needs 7th character
  24. O31.42
    Continuing pregnancy after vanishing twin syndrome of one fetus or more, second trimester New FY2027 +7th: 0 1 2 3 4 5 9
    Needs 7th character
  25. O31.43
    Continuing pregnancy after vanishing twin syndrome of one fetus or more, third trimester New FY2027 +7th: 0 1 2 3 4 5 9
    Needs 7th character
  26. O31.8
    Other complications specific to multiple gestation
    Header
  27. O31.8X
    Other complications specific to multiple gestation
    Header
  28. O31.8X1
    Other complications specific to multiple gestation, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  29. O31.8X2
    Other complications specific to multiple gestation, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  30. O31.8X3
    Other complications specific to multiple gestation, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  31. O31.8X9
    Other complications specific to multiple gestation, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character

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 O31

Excludes2

  • delayed delivery of second twin, triplet, etc. (O63.2) O63.2
  • malpresentation of one fetus or more (O32.9) O32.9
  • placental transfusion syndromes (O43.0-) O43.0

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 O31 defined here

One of the following 7th characters is to be assigned to each code under category O31. 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 a code from category O31 that has a 7th character of 1 through 9.

7th characters for O31
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

  • Papyraceous fetus → O31.0-
  • Fetus, fetalcompressus → O31.0-
  • Fetus, fetalpapyraceous → O31.0-
  • Syndromevanishing twin of one fetus or more → O31.4-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)papyraceous fetus → O31.0-
  • Pregnancy (single) (uterine)continuing followingspontaneous abortion of one or more fetus → O31.1-
  • Pregnancy (single) (uterine)continuing followingintrauterine death of one or more fetus → O31.2-
  • Pregnancy (single) (uterine)continuing followingelective fetal reduction of one or more fetus → O31.3-
  • Pregnancy (single) (uterine)continuing followingvanishing twin syndrome of one fetus or more → O31.4-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)death of fetus (near term)of one fetus or more in multiple gestation → O31.2-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)intrauterine fetal death (near term)multiple gestation (one fetus or more) → O31.2-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)fetal (maternal care for)reduction (elective) → O31.3-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)fetal (maternal care for)selective termination → O31.3-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)multiple gestationsspecified complication NEC → O31.8X-

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

Hierarchy