Conjoined twin pregnancy, third trimester

This code signifies a pregnancy involving conjoined twins that has progressed into the third trimester. Conjoined twins are a rare congenital anomaly where two fetuses are physically joined, often sharing organs or body structures. The third trimester spans from the 28th week of gestation until delivery.

Apply this code when documentation confirms a diagnosis of conjoined twin gestation and the patient is in her third trimester of pregnancy. This diagnosis is typically made via advanced imaging, such as detailed ultrasound or MRI. The medical record should clearly indicate the gestational age or trimester.

• Always confirm the specific trimester documented by the provider.
• Do not use this code for multiple gestations that are not conjoined (e.g., O30.00- for twin pregnancy, unspecified).
• Sequence this code as a primary diagnosis when it is the reason for the encounter, or as a secondary diagnosis when other conditions are being managed in the context of this high-risk pregnancy.