The diaphram and Sponge can reportedly have effectiveness rates of 90+% when used properly. Since 90+% isn’t all that great for some people, I was wondering if there is any research on how well various birth control products work with withdrawal?
I am aware that withdrawal on its own isn’t necessarily that good as some sperm can be released even prior to orgasm. Are there any studies that deal with this? I’ve looked but so far no luck.
Note: For purposes of this question STDs are not a concern.
Well, certainly successful withdrawal will lower the number of sperm present, thereby decreasing the likelihood of fertilization. But any studies would be damn tough to design, as it would be tough to assess success at withdrawal, which would need to be done within minutes. “excuse me, but we need a vaginal swab to see how many sperm are present. Please continue to lie still with your legs apart”. Not a realistic scenario.
And most people aren’t really interested in combining the withdrawal method with other BC’s anyway.
So empiricially I’d say it would have to reduce the odds of conception, but I doubt anyone will have much chance of coming up with a reliable estimate. Given that withdrawal actually fails (IE normal amounts of sperm are delivered intra-vaginally) about one out of ten times anyway, each episode of intercourse will be variable.
If you use 90% effectiveness for control method one, and a very loose estimate of 60% effectiveness for proper withdrawal, it’s a simple question of mathematics. You increase to about 96% effectiveness - but frankly I’m skeptical that anyone is practicing withdrawal in a manner consistent with the 60% number.