How do you tell your partner sex is uncomfortable?

Telling your partner something isn’t working during sex can be daunting—in fact, a 2019 study suggests only half of cis-women* tell their partners (predominantly men) something hurts while they’re gettin’ down.

Studies confirm: talking about sex generally leads to more fulfilling sex—from communicating desires to what's not-so-desirable! So, we want to know: how do you talk about it in the ~heat of the moment~?