Birth Control Failure Rates

[jl80]

would you say the sponge is a better form of birth control than spermicide alone?

[Brandye]

If you mean without the condom, maybe a little better. Theoretically the sponge absorbs the semen as it liquifies and kills the sperm swimming in it. In practical use, the "failure" of the sponge is about the same as spermicide alone.

Alone sponge equals about alone spermicide. Either one with condom is better than either one alone.

Barrier methods (condom, diaphragm, cervical cap) protect against that not often event that the man's urethral opening is directly against the cervical os upon discharge. The power of that first shot will get many sperm into the uterus without being exposed to spermicide. All those (400 million) sperm wandering around need to be captured by the spermicide because it is quite easy for sperm to swim around the edge of the diaphragm or, even, out the open end of a condom if you linger.

In short, all barrier methods REQUIRE chemical backup and the sponge has that onboard.

[arutha]

Originally Posted by Brandeye

protect against that not often event that the man's urethral opening is directly against the cervical os upon discharge. The power of that first shot will get many sperm into the uterus without being exposed to spermicide

Its probably not very much difference and I know there is always some chance, but does that mean there is more chance of pregnancy if you ejaculate right in front of the cervix opening than anywhere else in the vagina?

Not my main question though. Are diaphragms as effective as condoms in terms of BC? Or close to?

[Brandye]

Diaphragms, always used with vaginal jelly, have about the same effectiveness as condoms alone.

There is no way to measure exactly where the ejaculation took place relative the cervical os. But, if you line up the male urethra with the cervical os, there is a direct route into the uterus with that first, strong pulse.