DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

O41 Other disorders of amniotic fluid and membranes

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

O41 is not billable. The category heads 168 billable codes in FY2027, grouped under 4 subdivisions. Its codes take a 7th character, so none is complete with fewer than 7 characters.

Index → code

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. O41 Other disorders of amniotic fluid and membranes
Billable codes
168
Subdivisions
4
CC / MCC codes
21 / 63
HCC V28 codes
0
New FY2027
0
Index entries
22

Codes in O41

  1. O41.0
    Oligohydramnios
    Header
    Inclusion terms 1

    Inclusion terms

    • Oligohydramnios without rupture of membranes
  2. O41.00
    Oligohydramnios, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  3. O41.01
    Oligohydramnios, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  4. O41.02
    Oligohydramnios, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  5. O41.03
    Oligohydramnios, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterCC 0 1 2 3 4 5 9
  6. O41.1
    Infection of amniotic sac and membranes
    Header
  7. O41.10
    Infection of amniotic sac and membranes, unspecified
    Header
  8. O41.101
    Infection of amniotic sac and membranes, unspecified, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  9. O41.102
    Infection of amniotic sac and membranes, unspecified, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  10. O41.103
    Infection of amniotic sac and membranes, unspecified, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  11. O41.109
    Infection of amniotic sac and membranes, unspecified, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  12. O41.12
    Chorioamnionitis
    Header
  13. O41.121
    Chorioamnionitis, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  14. O41.122
    Chorioamnionitis, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  15. O41.123
    Chorioamnionitis, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  16. O41.129
    Chorioamnionitis, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  17. O41.14
    Placentitis
    Header
  18. O41.141
    Placentitis, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  19. O41.142
    Placentitis, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  20. O41.143
    Placentitis, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th characterMCC 0 1 2 3 4 5 9
  21. O41.149
    Placentitis, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  22. O41.8
    Other specified disorders of amniotic fluid and membranes
    Header
  23. O41.8X
    Other specified disorders of amniotic fluid and membranes
    Header
  24. O41.8X1
    Other specified disorders of amniotic fluid and membranes, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  25. O41.8X2
    Other specified disorders of amniotic fluid and membranes, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  26. O41.8X3
    Other specified disorders of amniotic fluid and membranes, third trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  27. O41.8X9
    Other specified disorders of amniotic fluid and membranes, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  28. O41.9
    Disorder of amniotic fluid and membranes, unspecified
    Header
  29. O41.90
    Disorder of amniotic fluid and membranes, unspecified, unspecified trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  30. O41.91
    Disorder of amniotic fluid and membranes, unspecified, first trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  31. O41.92
    Disorder of amniotic fluid and membranes, unspecified, second trimester +7th: 0 1 2 3 4 5 9
    Needs 7th character
  32. O41.93
    Disorder of amniotic fluid and membranes, unspecified, third 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 O41

Excludes1

  • encounter for suspected maternal and fetal conditions ruled out (Z03.7-) Z03.7

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 O41 defined here

One of the following 7th characters is to be assigned to each code under category O41. 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 O41 that has a 7th character of 1 through 9.

7th characters for O41
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

  • Oligohydramnios → O41.0-
  • Chorioamnionitis → O41.12-
  • Triple I → O41.12-
  • Placentitis → O41.14-
  • Infection, infected, infective (opportunistic)amniotic fluid, sac or cavity → O41.10-
  • Infection, infected, infective (opportunistic)intrauterine inflammation → O41.12-
  • Cyst (colloid) (mucous) (simple) (retention)amnion, amniotic → O41.8X-
  • Cyst (colloid) (mucous) (simple) (retention)chorion → O41.8X-
  • Fibrosis, fibroticamnion → O41.8X-
  • Fibrosis, fibroticchorion → O41.8X-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)oligohydramnios → O41.0-
  • Infection, infected, infective (opportunistic)amniotic fluid, sac or cavitychorioamnionitis → O41.12-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)amnionitis → O41.12-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)chorioamnionitis → O41.12-
  • Infection, infected, infective (opportunistic)amniotic fluid, sac or cavityplacentitis → O41.14-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)deciduitis → O41.14-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)placentitis → O41.14-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)infection(s)amniotic fluid or sac → O41.10-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)infection(s)intrauterine → O41.12
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)inflammationintrauterine → O41.12
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)disorders ofamniotic fluid and membranes → O41.9-
  • Pregnancy (single) (uterine)complicated by (care of) (management affected by)disorders ofamniotic fluid and membranesspecified NEC → O41.8X-

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

Hierarchy