I've tried them...the worst part was putting it in. No matter what i tried, it scraped a very sensitive area and stuck to my finger so that it was hard to put it in. Other than that, there is very little discomfort afterwards, it did cause me to get a little dry in the middle of intercourse so I ended up using lube anyway. I don't know if that affects the potency of the vcf, but I didn't get pregnant.
If I had to choose, I probably wouldn't use them again, only b/c I don't feel safe using only that. Now I'm on the pill and use condoms, but hey, whatever works for you, you know? Glad to be of some help.
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