12 weeks gestation of pregnancy

This code indicates that a patient is precisely 12 weeks into their pregnancy, as determined by the last menstrual period (LMP) or early ultrasound. It signifies the completion of the first trimester, a significant milestone in fetal development.

This code is used when documenting the gestational age of a pregnancy at 12 weeks. It is frequently applied during routine prenatal visits, particularly for the first trimester screening or dating ultrasounds that confirm this gestational age.

• Always confirm gestational age with physician documentation, prioritizing ultrasound measurements over LMP if there's a discrepancy.
• This code is typically used as a secondary diagnosis following the primary pregnancy code (e.g., O09.-).
• Do not use if the gestational age is anything other than exactly 12 weeks; use the appropriate Z3A.- code for other weeks.