Mat care chromosomal abnlt in fetus, Trisomy 13, fetus 5

This code signifies ongoing maternal care due to a suspected chromosomal abnormality in the fetus, specifically Trisomy 13 (Patau syndrome), identified in the fifth fetus of a multiple gestation pregnancy. Trisomy 13 is a severe genetic disorder characterized by the presence of an extra copy of chromosome 13, leading to significant developmental anomalies.

Apply this code when a pregnant patient is receiving antenatal care for a fetus (specifically the fifth fetus in a multiple gestation) with a suspected diagnosis of Trisomy 13. Documentation should clearly indicate the suspected chromosomal abnormality, the specific type (Trisomy 13), and the fetal number in a multifetal pregnancy.

• Always sequence this code as a secondary diagnosis following a code from category Z3A (Gestational age) and potentially O09 (Supervision of high-risk pregnancy).
• Ensure the medical record explicitly states "suspected" or "probable" Trisomy 13; if confirmed, a different code for confirmed fetal anomaly would be used.
• Verify the fetal number (e.g., fetus 1, 2, 3, 4, 5, or other) to ensure the correct fifth-character extension is selected for multiple gestations.