From the 2007-08 National Survey on Drug Use and Health:
[The following question is asked separately for each illicit drug: marijuana or hashish, cocaine, "crack," heroin, hallucinogens, and inhalants:]
How long has it been since you last used [marijuana or hashish, cocaine, "crack," heroin, hallucinogens, inhalants]?
Marijuana or Hashish
[The following questions are asked separately for nonmedical use of analgesics (prescription pain killers), tranquilizers, stimulants, and sedatives:]
How long has it been since you last used (a pain killer, tranquilizers, stimulants, sedatives) that was not prescribed for you, or that you took only for the experience or feeling it caused?
Are you currently pregnant?
How many months pregnant are you?
Number of months pregnant _____