how would someone is pregnant not menstrate
If you were pregnant then you wouldn't menstruate at all. Menstruation only occurs if there is no pregnancy, if you menstruate you're not pregnant.
It is biologically impossible to menstruate if you were pregnant.
If you menstruate then you're not pregnant - it is possible to bleed while pregnant, but it is biologically impossible to menstruate while pregnant. The very earliest you can tell when you're pregnant or not is 3 weeks after you had sex, via pregnancy test.
This makes no sense - you only menstruate if you don't fall pregnant. It's also unlikely you'd be fertile so close to when you were due to menstruate.
ten days menstrate
No, it is biologically impossible to menstruate while you are pregnant.
It is biologically impossible to menstruate if you are pregnant, menstruation only occurs if someone doesn't get pregnant. It is possible to experience vaginal bleeding during pregnancy, it's uncommon but there are situations where it can happen, if concerned you may be pregnant take a pregnancy test.
No, it's biologically impossible for a woman to menstruate while she is pregnant - a woman will only menstruate if she doesn't get pregnant during the last cycle. A woman can bleed during pregnancy for various reasons but this is fairly rare, chances are if you're menstruating you're not pregnant.
Yes, Menstruation can also occur while pregnant, unless if she has menstruation disabilities.