6. Agree to use the study product as instructed at each act of intercourse during the next 30 weeks and to use no other method of contraception (Except: 1) ECPs when indicated, see Section VIII.C.5, or, 2) a barrier method (e.g. Gynol II, condoms) from pre-enrollment until the start of the first post-enrollment menses, see Section VIII.B.4).