You do you. Some people like to wear period underwear as a backup, like a soft-to-the-touch insurance policy, along with tampons or a menstrual cup.
But please know that, with our Tri-Tech technology, our pants are designed to be fully relied on –– as long as you choose the absorbency level that best works for you. There is no 'need' to wear a pad or tampon with your period pants, but if it helps make you feel comfortable, then go for it.