Chorioamnionitis, first trimester, not applicable or unsp

This code signifies an inflammatory condition of the fetal membranes (amnion and chorion) and amniotic fluid, occurring during the first trimester of pregnancy. It indicates an infection within the gestational sac, which can pose risks to both the mother and the developing fetus.

Apply this code when documentation explicitly states chorioamnionitis diagnosed in the first trimester, without further specification of the type or if the information is not applicable. This code is appropriate when the medical record confirms the presence of this infection early in gestation.

• Ensure documentation clearly specifies "first trimester" for accurate code assignment.
• Avoid using this code if the chorioamnionitis is specified as acute or chronic; instead, use the more specific codes in the O41.12 subcategory.
• Always sequence this code as a primary diagnosis when it is the reason for the encounter, or as a secondary diagnosis if it is a co-morbidity affecting the pregnancy.