Does the use of male condoms combined with vaginal administration of spermicide significantly improve effectiveness?
Estimates from mathematical modeling suggest that the contraceptive failure rate in couples with simultaneous “perfect” use of condoms and separately applied vaginal spermicide is reduced to 0.1 percent, the same rate as that associated with perfect use of the combined oral contraceptive. The use of intravaginally applied spermicide, in contrast to spermicide incorporated in condoms, guarantees its presence in the vaginal region in the unlikely case of condom breakage or leakage. Some spermicides incorporate chemicals with additional viricidal properties that may also afford additional protection from viral sexually transmitted diseases (STD) in the event of condom breakage.
