No, they haven't. And women's safe periods isn't that safe either.
Interim Periods
yes
when is the right time to put copper t as a contraceptive, is it during monthly periods
no, this you be checked by a doctor
No.
Generally speaking no, you need to determine why you are not having monthly periods, but no period usually means you are not ovulating.
Menses same as Periods
Paid once a month (12 pay periods per year)
Paid twice a month (24 pay periods a year)
Yes. it is possible. A woman can have a few periods or even regular monthly periods during pregnancy.
Yes but they are far less likely to get it then men until after menopause.