Drug use complicating pregnancy, first trimester

This code signifies the presence of drug use (illicit or prescription drug misuse) in a pregnant patient during her first trimester, where the drug use is considered a complication of the pregnancy. It indicates that the substance use is impacting or has the potential to impact the course or outcome of the pregnancy.

Apply this code when documentation clearly indicates a pregnant patient in her first trimester is actively using or has a history of drug use that is complicating the pregnancy. This includes scenarios such as substance use disorder, withdrawal symptoms, or drug-related medical conditions affecting the pregnancy. Supporting documentation would include physician notes detailing drug use, toxicology screens, and an explicit link between the drug use and the pregnancy complication.

• Always sequence this code after the primary obstetric code (e.g., O09.- for supervision of normal pregnancy) if the drug use is a complication.
• Do not use this code for drug use that is not complicating the pregnancy; instead, use codes from Chapter 5 (F11-F19) for substance-related disorders.
• Ensure the documentation specifies "first trimester" to accurately assign this specific code; otherwise, use O99.322 or O99.323 for subsequent trimesters.