Where do you get the condom is only 84% effective? If you use a condom by itself then it is around 86% effective so you are close but if the condom is used with spermicidal agents it is over 95‰ effective. The condoms that are given out at the health department contain spermicidal agents. They also hand out condoms made of lambskin and polyurethane in case you are allergic to latex.
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