She is not a pilot but she stated that women make less good pilots because during their period they tend to be very short-tempred or getting angry much more easily. Obviously her not being a pilot her argument does not hold a lot ot water but nervertheless it does show something...
My neighbour thinks that the moon is made of green cheese. This does show something...
I believe that often PMS or dysmynoria are merely excuses, and a woman that is happy about herself doesn't really suffer.
Feel free to believe what you like, including that the earth is flat or helicopters fall like a stone when the engine fails. Don't let facts stop you.