No, clearly it's not possible for a woman to menstruate while pregnant.Menstruation is the process of the uterus lining shedding as a result of a woman not falling pregnant. A woman can bleed during pregnancy but she will not menstruate.
Typically, a woman of childbearing age should menstruate every 28 days or so unless she is pregnant or moving into menopause.
Menstruation is body getting rid of the egg. If the egg is fertilized, the woman is pregnant, the body will not get rid of it.
Conceive refers to an egg being fertilized, which then goes on to implant which means that a woman is pregnant. If a woman is pregnant then she will not menstruate, menstruation only occurs if conception doesn't occur.
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.
It may mean you are pregnant, have a hormonal imbalance or are experiencing irregular periods.
If a girl thinks she is pregnant that doesn't mean that she is pregnant. A woman cannot menstruate while she is pregnant, thus if she menstruates she obviously isn't pregnant even if she thinks otherwise - although women can bleed during pregnancy this is uncommon, and not menstruation.