Social & Preventive Medicine FMGE 2018 4b4190c9 Highest Contraceptive failure is repoed in A Spermicidal methods B Implant C Oral contraceptive pills D IUD High-Yield Explanation - Spermicidal methods has pearl index of 10-25 / HWY ( Highest ). - Contain chemical - Non oxynol 9 - MOA - By rupture of plasma membrane of Acrosomal cap.