Q89.4 Conjoined twins

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis. Exempt from present-on-admission (POA) reporting.

Applicable to

• Craniopagus
• Dicephaly
• Pygopagus
• Thoracopagus

MS-DRG index

Defines the logic of DRG(s) 393-395 in MDC 06.

Approximate ICD-9-CM (GEMs)

• 759.4 Conjoined twins

Diagnosis Index entries for Q89.4

• Conjoined twins
• Craniopagus
• Dicephalus, dicephaly
• Double › monster
• Epignathus
• Fusion, fused (congenital) › twins
• Ischiopagus
• Janiceps
• Monster, monstrosity (single) › twin
• Parasitic › twin
• Pygopagus
• Rudimentary (congenital) › respiratory organs in thoracopagus
• Siamese twin
• Sternopagus
• Syncephalus
• Thoracopagus
• Twin (newborn) › conjoined
• Xiphopagus

Nearby codes

• Q89.01 Asplenia (congenital)
• Q89.09 Congenital malformations of spleen
• Q89.1 Congenital malformations of adrenal gland
• Q89.2 Congenital malformations of other endocrine glands
• Q89.3 Situs inversus
• Q89.4 Conjoined twins (this code)
• Q89.7 Multiple congenital malformations, not elsewhere classified
• Q89.8 Other specified congenital malformations
• Q89.81 Kabuki syndrome
• Q89.89 Other specified congenital malformations
• Q89.9 Congenital malformation, unspecified