In simple words: This code is used when a mother's drug use causes problems during her pregnancy's third trimester (the last three months).Doctors will also use codes to describe the specific drug and its effects on the mother.

This code classifies drug use that complicates pregnancy specifically during the third trimester (28 weeks 0 days gestation until delivery).Additional codes from categories F11-F16 and F18-F19 should be used to specify the type of drug used and its manifestations. This code is for maternal records only; it should not be used on newborn records.The code encompasses conditions that complicate the pregnant state, are worsened by pregnancy, or are a primary reason for obstetric care.It excludes cases where the reason for maternal care is due to suspected or known effects on the fetus.

Example 1: A 35-year-old pregnant woman at 32 weeks gestation presents with symptoms of opioid withdrawal.She admits to using heroin throughout her pregnancy.O99.323 would be used along with codes to specify the opioid and its effects on the mother., A 28-year-old pregnant woman at 36 weeks gestation is admitted for pre-eclampsia, worsened by her long-term cocaine use.O99.323 would be used to capture the complication related to drug use in the third trimester, along with a code for pre-eclampsia., A 40-year-old pregnant woman at 30 weeks gestation is admitted for methamphetamine-induced cardiomyopathy. O99.323 would be used alongside codes for cardiomyopathy and the effects of methamphetamine.

Detailed documentation is required, including the type of drug used, the frequency and duration of use, any withdrawal symptoms, and maternal complications directly resulting from the drug use.Supporting lab results (e.g., toxicology screens) and clinical findings should be documented.

** This code is specifically for the third trimester of pregnancy.Use appropriate codes for drug use complicating other stages of pregnancy or postpartum.