Does the cap or diaphragm cause cystitis?

I've used Caya several times over the past couple years (they last up to 2 years- due for a new one now). I use it on the edges of my fertile window (with fertility awareness) and/or combined with withdrawal or condoms to boost efficacy during the fertile window. Always use with Caya/Contragel- they come with an applicator to re-insert the gel into the vagina, as you need to reapply the gel each time you have sex. Watching the YouTube instructions on how to put it in (plus the instruction manual in the box!) helped me understand how to use it properly and to have an idea of how it was inserted properly.

Having experienced terrible physical and mental health side effects from both types of contraceptive pill (Combined and POP), and permanent pain and repeated UTIs with the copper coil, I hoped that Caya diaphragm would be a suitable non-hormonal method to try. Unfortunately, I found insertion very tricky - it seems I have a case of "deep vagina, small fingers", as I could never tell whether I'd pushed the diaphragm up far enough to cover my cervix, and sex was always a bit uncomfortable. I'm naturally prone to cystitis and thrush, and getting both while using the diaphragm also put me off using it long term. However, on the plus side - I didn't get pregnant (though I was still breastfeeding a lot, and my periods hadn't yet returned postpartum), and I did manage to avoid the hormonal depression, skin changes and weight gain/loss that I've experienced in the past with pills.

All in all it was acceptable