ICD-10-CM Code First Notes · Chapter 15 · FY 2027 O00-O9A

Code First Notes in Chapter 15: Pregnancy, childbirth and the puerperium ICD-10-CM

A Code First note means the underlying condition named in the note is sequenced before this code. In Chapter 15 (O00-O9A), notes printed in the chapter name other codes 5 times, and Code First Notes anywhere in the Tabular List name the chapter’s codes 51 times, covering 28 distinct codes, categories and ranges. Switch views to read the list either way.

✓ From the official FY 2027 ICD-10-CM Tabular ListDefinitions follow the Official Guidelines, Section I.A
5
References in Its Notes
51
References to Its Codes
28
Chapter Codes Named
O00-O9A
Chapter 15
Chapter 15

Code First Notes by the code that carries the note

3 of 3 shown
  • O34 Maternal care for abnormality of pelvic organs applies to 54 codes
    • any associated obstructed labor (O65.5)
  • O66.41 Failed attempted vaginal birth after previous cesarean delivery
  • O75.82 Onset (spontaneous) of labor after 37 completed weeks of gestation but before 39 completed weeks gestation, with delivery by (planned) cesarean section
    • cephalopelvic disproportion (normally formed fetus) (O33.9)
    • previous cesarean delivery (O34.21-)

The first view lists notes printed in this chapter (a note on a category or block applies to every code beneath it). The second lists codes of this chapter named by Code First Notes anywhere in the Tabular List, including notes in other chapters.

Questions About Code First Notes

What does a Code First note mean?

A Code First note means the underlying condition named in the note is sequenced before the code that carries the note. Under the etiology/manifestation convention, a “code first” note appears at the manifestation code and a “use additional code” note at the etiology code (Section I.A.13). The FY 2027 Tabular List has 810 of them; 600 name other codes, with 736 references to 429 distinct codes, categories and ranges.

Can a code with a Code First note be the principal diagnosis?

Not when it is a manifestation code. Codes titled “in diseases classified elsewhere” are never permitted as the first-listed or principal diagnosis; they must follow the underlying condition. The etiology and manifestation page lists them all.

Related References

ICD-10-CM Official GuidelinesICD-10-CM Code LookupICD-10-CM Codes ListCode Lists by Tag

Source: FY 2027 ICD-10-CM Tabular List (CMS and NCHS) and the ICD-10-CM Official Guidelines for Coding and Reporting FY 2027, Section I.A. ICD List is not affiliated with CMS or NCHS.