Within 3 days before the start of each cycle, on Day 3 of each cycle, and then one time during Weeks 2 and 3 of each cycle (if the doctor thinks it is needed), blood (about 2 tablespoons) will be drawn for routine tests and to check your kidney and liver function. Part of this blood sample will be used for a pregnancy test if you can become pregnant. Urine may also be collected for this pregnancy test.