- An unwillingness to abstain from sexual intercourse with pregnant or lactating women; or an unwillingness of the subject to use a condom/spermicide in addition to having their female partner use another form of contraception such as an IUD, diaphragm with spermicide, oral contraceptives, injectable progesterone, sub dermal implants or a tubal ligation if the women could become pregnant from the time of the first dose of the study medication until completion of the follow-up procedures.