O66.4
Failed trial of labor
Not billable — category only FY2026 2025-10-01 → 2026-09-30
Exclusions 5 never code together
O00-O9Achapter
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 7
O00-O9Achapter
Notes
- CODES FROM THIS CHAPTER ARE FOR USE ONLY ON MATERNAL RECORDS, NEVER ON NEWBORN RECORDS
- Codes from this chapter are for use for conditions related to or aggravated by the pregnancy, childbirth, or by the puerperium (maternal causes or obstetric causes)
- Trimesters are counted from the first day of the last menstrual period. They are defined as follows:
- 1st trimester- less than 14 weeks 0 days
- 2nd trimester- 14 weeks 0 days to less than 28 weeks 0 days
- 3rd trimester- 28 weeks 0 days until delivery
Use additional code
- code, if applicable, from category Z3A, Weeks of gestation, to identify the specific week of the pregnancy, if known.Z3A
Index entries leading here filed at null
No alphabetic index entry points at this code.
Alongside this code 8 same parent — O66
O66.0 Obstructed labor due to shoulder dystocia O66.1 Obstructed labor due to locked twins O66.2 Obstructed labor due to unusually large fetus O66.3 Obstructed labor due to other abnormalities of fetus O66.5 Attempted application of vacuum extractor and forceps O66.6 Obstructed labor due to other multiple fetuses O66.8 Other specified obstructed labor O66.9 Obstructed labor, unspecified
Subordinate codes 2
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.