O66.9 Obstructed labor, unspecified

Billable ICD-10-CM code, FY2026.

Applicable to

• Dystocia NOS
• Fetal dystocia NOS
• Maternal dystocia NOS

MS-DRG index

Defines the logic of DRG(s) 817-819 in MDC 14.

Approximate ICD-9-CM (GEMs)

• 660.91 Unspecified obstructed labor, delivered, with or without mention of antepartum condition (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Maternity diagnoses (age 9 through 64): Age conflict edit. These diagnoses are clinically expected only in patients age 9 through 64.

Code annotations containing back-references to O66.9

Back-references to O66.9

• Type 1 Excludes: O62.4 Hypertonic, incoordinate, and prolonged uterine contractions ("dystocia (fetal) (maternal) NOS (O66.9)")

Back-references to O66

• Type 1 Excludes: O33 Maternal care for disproportion ("disproportion with obstructed labor (O65-O66)")

Diagnosis Index entries for O66.9

• Delay, delayed › any plane in pelvis › complicating delivery
• Delivery (childbirth) (labor) › complicated › by › obstructed labor › due to › dystocia (fetal)
• Dystocia
• Dystocia › fetal
• Dystocia › maternal

Nearby codes

• O66.40 Failed trial of labor, unspecified
• O66.41 Failed attempted vaginal birth after previous cesarean delivery
• 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 (this code)