Oligohydramnios, first trimester, fetus 4

This code signifies a lower than normal volume of amniotic fluid surrounding the fetus during the first trimester of pregnancy, specifically identifying the fourth fetus in a multiple gestation. Oligohydramnios can indicate potential fetal renal anomalies, placental insufficiency, or membrane rupture, even in early pregnancy.

Apply this code when documentation confirms oligohydramnios diagnosed in the first trimester (up to 13 weeks and 6 days gestation) for the fourth fetus in a multifetal pregnancy. This diagnosis is typically made via ultrasound measurement of the amniotic fluid index (AFI) or deepest vertical pocket (DVP).

• Ensure the documentation clearly specifies "first trimester" and identifies the "fourth fetus" in a multiple gestation.
• Do not use this code if the oligohydramnios is diagnosed in the second or third trimester; specific codes exist for those periods.
• Always sequence this code as a secondary diagnosis following the primary code for the pregnancy, such as Z3A.00 for weeks of gestation.