I've been browsing and didn't see this specifically asked. I've been using a menstrual cup for several years with general success, but still have some leaking issues. The first couple of days are pretty good, but by the 3rd and 4th day I tend to get leaking of fresh blood (not the "residual slobber" I've seen referenced, lol) when there is hardly anything in the cup. It's like my menstrual fluid is so much thinner that it slips right by the cup or something. I notice this especially when I am sitting or lying down.
I'm currently using a large Lunette, but have also used a Diva Cup, Fleurcup, and Sckoon Cup with the same general issues. I have a relatively low cervix, and am 30 with no kids. I also believe I have a tilted uterus, if that's relevant.
I don't really know what the problem is – if the cup is migrating too high and my cervix is just taking up a bunch of room (seems unlikely since I don't have much of a problem the first few days of my period), or if the cup is too stiff (Lunette especially) and just isn't bending with my body, or if it's somehow not stiff enough and my body crushes it, or something else I haven't thought of. I don't specifically think it's a pelvic floor muscle issue since I only have trouble some days?
A cup still beats tampons, but I'm frustrated because I feel like I can never trust it without a liner on, and will often get a little gush of blood and have to go deal with it. Any specific thoughts? Thanks to anyone who can offer insight! :)