Hi! i would like to know does smoking marijuana lessen the effect of the nonhormonal birth control phexxi in reguards to preventing pregnancy?

Smoking Marijuana can have many adverse effects within the body, but because Phexxi is a topical spermicide which changes the PH in the vagina, it does not have a direct effect. Remember that Phexxi is only about 80% effective in preventing pregnancy and lasts only 1 hour or one ejaculation. Using a condom or other contraceptive method would result in less risk of pregnancy.