U.S. category index · FY 2027

O ICD-10-CM Categories: Category Index

Browse 72 top-level ICD-10-CM categories beginning with O, then follow their complete FY 2027 child-code hierarchies.

Complete category list

Categories beginning with O

Open a category to continue through its complete hierarchy of more specific codes.

O00

Ectopic pregnancy

O01

Hydatidiform mole

O02

Other abnormal products of conception

O03

Spontaneous abortion

O04

Complications following (induced) termination of pregnancy

O07

Failed attempted termination of pregnancy

O08

Complications following ectopic and molar pregnancy

O09

Supervision of high risk pregnancy

O10

Pre-existing hypertension complicating pregnancy, childbirth and the puerperium

O11

Pre-existing hypertension with pre-eclampsia

O12

Gestational [pregnancy-induced] edema and proteinuria without hypertension

O13

Gestational [pregnancy-induced] hypertension without significant proteinuria

O14

Pre-eclampsia

O15

Eclampsia

O16

Unspecified maternal hypertension

O20

Hemorrhage in early pregnancy

O21

Excessive vomiting in pregnancy

O22

Venous complications and hemorrhoids in pregnancy

O23

Infections of genitourinary tract in pregnancy

O24

Diabetes mellitus in pregnancy, childbirth, and the puerperium

O25

Malnutrition in pregnancy, childbirth and the puerperium

O26

Maternal care for other conditions predominantly related to pregnancy

O28

Abnormal findings on antenatal screening of mother

O29

Complications of anesthesia during pregnancy

O30

Multiple gestation

O31

Complications specific to multiple gestation

O32

Maternal care for malpresentation of fetus

O33

Maternal care for disproportion

O34

Maternal care for abnormality of pelvic organs

O35

Maternal care for known or suspected fetal abnormality and damage

O36

Maternal care for other fetal problems

O40

Polyhydramnios

O41

Other disorders of amniotic fluid and membranes

O42

Premature rupture of membranes

O43

Placental disorders

O44

Placenta previa

O45

Premature separation of placenta [abruptio placentae]

O46

Antepartum hemorrhage, not elsewhere classified

O47

False labor

O48

Late pregnancy

O60

Preterm labor

O61

Failed induction of labor

O62

Abnormalities of forces of labor

O63

Long labor

O64

Obstructed labor due to malposition and malpresentation of fetus

O65

Obstructed labor due to maternal pelvic abnormality

O66

Other obstructed labor

O67

Labor and delivery complicated by intrapartum hemorrhage, not elsewhere classified

O68

Labor and delivery complicated by abnormality of fetal acid-base balance

O69

Labor and delivery complicated by umbilical cord complications

O70

Perineal laceration during delivery

O71

Other obstetric trauma

O72

Postpartum hemorrhage

O73

Retained placenta and membranes, without hemorrhage

O74

Complications of anesthesia during labor and delivery

O75

Other complications of labor and delivery, not elsewhere classified

O76

Abnormality in fetal heart rate and rhythm complicating labor and delivery

O77

Other fetal stress complicating labor and delivery

O80

Encounter for full-term uncomplicated delivery

O82

Encounter for cesarean delivery without indication

O85

Puerperal sepsis

O86

Other puerperal infections

O87

Venous complications and hemorrhoids in the puerperium

O88

Obstetric embolism

O89

Complications of anesthesia during the puerperium

O90

Complications of the puerperium, not elsewhere classified

O91

Infections of breast associated with pregnancy, the puerperium and lactation

O92

Other disorders of breast and disorders of lactation associated with pregnancy and the puerperium

O94

Sequelae of complication of pregnancy, childbirth, and the puerperium

O98

Maternal infectious and parasitic diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

O99

Other maternal diseases classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

O9A

Maternal malignant neoplasms, traumatic injuries and abuse classifiable elsewhere but complicating pregnancy, childbirth and the puerperium

Transparency

Source and release

Data release

U.S. ICD-10-CM · FY 2027

Effective date

Oct 1, 2026

This category index is generated from Vero’s repository-backed ICD-10-CM hierarchy. Every listed category is a top-level record, and each linked category page exposes its direct child codes.

Review the CDC/NCHS ICD-10-CM source

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Frequently asked questions

Which ICD-10-CM categories begin with O?

This index lists 72 top-level categories beginning with O from Vero’s FY 2027 U.S. ICD-10-CM reference dataset.

How do I find a more specific O code?

Open a category below, then follow its linked child-code hierarchy until you reach the code supported by the documentation.

Which ICD-10-CM release does this O index use?

The index uses the FY 2027 U.S. ICD-10-CM release and the repository-backed hierarchy displayed on each linked code page.

Is every O category billable?

No. These are top-level categories used for navigation. Follow the hierarchy to a sufficiently specific code and confirm the active code set, official guidance, and payer requirements.

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