Infct of amniotic sac and membrns, unsp, unsp tri, fetus 4

This code signifies an infection of the amniotic sac and membranes (chorioamnionitis) occurring during pregnancy, where the specific trimester of onset is not documented. It indicates that the infection is affecting the fourth fetus in a multiple gestation pregnancy.

Use this code when documentation confirms chorioamnionitis in a multifetal pregnancy (quadruplets or more), and the specific trimester of diagnosis is not specified. The medical record must clearly identify the affected fetus as the fourth in the sequence.

• Ensure documentation specifies "fetus 4" in a multiple gestation. If the fetus number is not specified, a different code may be appropriate.
• Avoid using this code if the trimester of infection is known; instead, select the trimester-specific code (e.g., O41.114, O41.124, O41.134).
• Always sequence this code after the primary obstetric complication if applicable, and ensure it is linked to the appropriate Z3A code for gestational age.