Usually anywhere from three to five days.
No women fail to menstruate. It comes naturally.
Their body
No, only people with female reproductive systems menstruate.
No, transwomen do not have uteruses or ovaries. Transwomen cannot menstruate or bear children.
yes
They had peasant women menstruate for them!
I'm not sure what you mean asking if it 'gets to them'. Most women menstruate, this is a normal occurrence so no reason for it to bother other women when you menstruate.
They suffer iron loss when they menstruate.
Some rough figures... 7,000,000,000 people on the planet = 3,500,000,000 women. 70% of those will be either pre-pubescent or post-menopausal. Leaving 1,050,000,000 possibilities. Divide that by the number of days in a year - and you get the averagefigure of 2,874,743
No, not every female gets her period. If talking exclusively of those who are biologically female there are those who don't have the anatomy to menstruate or their bodies don't produce the hormones needed to have a menstrual cycle. Pre-pubescent girls don't menstruate and women past menopause don't menstruate, also women who are pregnant won't menstruate during pregnancy (sometimes for longer if they breastfeed), and women who have a hysterectomy to remove the uterus.
It is biologically impossible to menstruate if you were pregnant.
Until around fifty it is not true that if a women get her period early in life she will go through menopause earlier