Chance of pregnancy?

Andrea

<a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> is telling me that my chance of pregnancy is 27% (which is laughable, I haven’t had sex in 9 months and I’ve gotten my period every month since then. I’m also obviously not pregnant...)!

Is this specific to the fertile window part of my cycle? Like, is it saying that if I were to have sex today I would have a 27% chance of getting pregnant? I’m just trying to figure out how they come up with this number and what it means.