Mat care chromsoml abnlt in fetus, sex chromo abnlt, fetus 1

This code signifies maternal care provided due to a suspected or confirmed sex chromosome abnormality in the first fetus of a multiple gestation pregnancy. This includes conditions such as Turner syndrome (XO), Klinefelter syndrome (XXY), or other aneuploidies involving the X or Y chromosomes. The maternal care is specifically for monitoring and managing the pregnancy in light of this fetal condition.

Use this code when the mother is receiving antenatal care for a fetus diagnosed or suspected to have a sex chromosome abnormality, and it is the first fetus identified in a multifetal pregnancy. Documentation should clearly indicate the suspected or confirmed sex chromosome abnormality and specify that it pertains to fetus 1. This code is appropriate when diagnostic tests like amniocentesis, chorionic villus sampling (CVS), or non-invasive prenatal testing (NIPT) suggest such an anomaly.

• Ensure documentation specifies "fetus 1" for accurate assignment in multiple gestations.
• Do not use this code if the chromosomal abnormality is autosomal; refer to other O35.1x codes.
• Sequence this code as a secondary diagnosis when the primary reason for the encounter is routine prenatal care.