- If the subject is a female and of childbearing potential, or less than 2 years post-menopausal, she must have been using adequate contraception during her last menses and will use adequate contraception during the study, is not lactating, and has had a negative urine pregnancy test within 24 hours prior to receiving the first dose of study medication. Women less than two years post-menopausal are considered of childbearing potential for the purposes of this study.