They are great to pair with jeans and on heavy flow days too. (myntra.com)
I bought the medium size - perfect size for overnight and the first couple heavier flow days for me. (diaperjunction.com)
No need to change anything if you've found something that works well for you, but a lot of women who use menstrual cups wear period underwear as backup on heavier flow days. (nicolejardim.com)