Chorioamnionitis, second trimester, fetus 1

This code signifies an infection of the fetal membranes (amnion and chorion) and amniotic fluid occurring during the second trimester of pregnancy, specifically affecting the first fetus in a multiple gestation. Chorioamnionitis is a serious complication that can lead to preterm labor, fetal distress, and maternal sepsis.

Apply this code when documentation confirms chorioamnionitis diagnosed in the second trimester (weeks 14-27+6 days) and the patient is carrying twins, triplets, or higher-order multiples, with the infection attributed to the first identified fetus. Supporting documentation should include clinical signs of infection (e.g., fever, uterine tenderness, foul-smelling amniotic fluid), laboratory findings (e.g., elevated white blood cell count), and/or amniocentesis results.

• Ensure the trimester is clearly documented as the second trimester.
• Verify that the documentation specifies "fetus 1" in cases of multiple gestations.
• Do not confuse with O41.12X0 for a single gestation or O41.12X9 for unspecified fetus in a multiple gestation.