Hahahaha i never tried em! Just elevated my hips :)
Oh my gosh, I totally forgot about those. I actually bought some after reading about them a few years back. Like you, I heard that they could be used to keep the sperm close to the cervix to help them along, so to speak. I figured it was worth a try. Not so much. I couldn't even get it in right. I don't even get how people can use those things for their period. But who knows, maybe it's just me :-)
That is a menstrual cup that some women use during their period.
Google it