Vaginal application gels or foams are meant to be used before intercourse occurs. However, I was wondering if they reduce pregnancy risk at all, if applied soon after intercourse? I haven't been able to find any info--is it that no studies have been done on the matter? Thanks!
According to our article on Spermicides "they are even more likely to fail if they are not inserted before intercourse, or early enough for some methods -- namely, film -- also sometimes called VCF -- or suppositories, which are not effective instantly like foam or jellies are." In other words, you don't see people really discussing using a spermicide after sex because it makes the method less effective.
Just to be clear, once sperm cells get into the cervix, which is almost immediate after ejaculation, spermicide can’t do anything, because it is in the vagina, not inside the cervix or the rest of the uterus.
In order for spermicide to work, it has to have contact with the sperm cells. It can’t do that used after intercourse (presuming you also mean after ejaculation) because the best of those cells - which are the ones with the capacity to fertilize an egg - have already moved past the vagina and into the cervix.
Make sense?
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has. - Margaret Mead