My last couple of cycles though, using the cup for the whole thing, I've had some leaking issues. Last cycle, I had the cup in for about 6 hours on one of my heavier days, when it started leaking spontaneously and rapidly. When I looked to see what the problem was, it was fairly full, but I don't think to the point of overflow. I have my period right now as well and have had the same issue a couple of times. Last night I was just sitting on the couch with my partner, it had been fine for about 4 hours or so, no leaks or problems, when I felt the cup start to leak so immediately went and emptied it. This morning when I woke up, as well, I realized that the cup had started leaking shortly before I woke up. I think it would have been in for about 8 hours total. Both times, the cup was only about half full, maybe a little more. Not as full as it was the first time that happened, and I don't think anywhere near full enough it should be overflowing...I'm puzzled.
I'm 21 using a size 1 Diva Cup - never had kids and also always had a fairly "tight" vagina, and my pelvic muscles are all strong enough that when defecating with the cup in, I have to put my finger on the end of the stem to hold it in place so I don't push that out as well. Sometimes even a strong cough, I need to clench it in place so it doesn't get pushed down. Maybe a little TMI, but my point is, I don't think the leakage issues are due to weak muscles or improper placement. I always sweep around with my finger to make sure the cup is properly open and situated, and as I've said, the cup will be totally fine for several hours before leaking occurs.
I did read a few posts regarding a "dangly" cervix taking up space in the cup, and causing it to overflow before it should. However, I've never even been able to really feel my cervix with my finger, it's too far up. So, I don't think that's the problem either. As well, as mentioned before, the cup has been varying levels of fullness when this spontaneous leaking occurs.
Anyhow - I did email their customer support, explaining the problem in detail, and they very unhelpfully sent back a copy/paste of the success tips and FAQs that I had already read on the website. I love my Diva Cup for many reasons, and I don't want to go back to tampons and pads, but I may have to if I can't figure out this random leaking issue. So sorry for the long post, but I'm really hoping someone can help me out here! Has anyone else experienced this, or have any idea what the problem might be? Thanks in advance!