Femcare is an organisation in Canada which provides education and advocacy around periods, seeks to end period poverty and end the stigma and health issues associated with periods.
Look at this tweet in their series about PCOS: 'another complication that may arise as a result of polycystic ovary syndrome is a menstruator having a miscarriage or premature birth of the baby'
A woman who is pregnant is not menstruating you fucking idiots. 
This is where this shitty language gets us. Organisations which are created and funded for women's health have completely erased us.
We are menstruators, birth givers, ovary havers.
Ps I am gratified to see that my iPad doesn't like the word menstruator. I'm sure that will change with the next update 