- Women of childbearing potential must have a negative serum or urine pregnancy test with a sensitivity of at least 50 mIU/mL within 10 to 14 days prior to therapy and repeated within 24 hours before starting study drug. They must commit to continued abstinence from heterosexual intercourse or begin 2 acceptable methods of birth control (1 highly effective method and 1 additional effective method) used at the same time, beginning at least 4 weeks before initiation of Revlimid treatment. Women must also agree to ongoing pregnancy testing