<qa>  What is the most effective method of contraception?1. Do not agree to use a highly effective method of contraception ie, total abstinence, if it is their preferred and usual lifestyle, an intrauterine device or intrauterine system, a contraceptive implant, an oral contraceptive, or have a vasectomized partner with confirmed azoospermia within 30 days before study entry and throughout the entire study period and for 30 days after study drug discontinuation. 