Amniotic fluid embolism in pregnancy, first trimester

This code signifies a rare, life-threatening obstetric emergency where amniotic fluid, fetal cells, hair, or other debris enters the maternal bloodstream during the first trimester of pregnancy. This triggers an anaphylactoid reaction, leading to cardiovascular collapse, respiratory distress, and coagulopathy. It represents a severe systemic inflammatory response to fetal material.

Assign this code when documentation clearly indicates an amniotic fluid embolism occurring in a pregnant patient during her first trimester. Supporting documentation should detail the acute onset of symptoms such as sudden hypotension, hypoxia, and disseminated intravascular coagulation (DIC) in the context of pregnancy. This diagnosis is typically made clinically based on the rapid deterioration of the patient.

• Ensure the documentation explicitly states "first trimester" for accurate code assignment.
• Do not confuse this with other types of embolisms (e.g., pulmonary embolism) unless amniotic fluid is specifically identified as the embolic material.
• Always sequence this code as a principal diagnosis when it is the primary reason for the encounter, followed by codes for associated complications like DIC (D65) or cardiac arrest (I46.2).