Does Masturbation Or Sex Or Anything That Ends With An Orgasm Cause Menstruation To Happen Sooner?

Hello, this is such an awkward medical query but yahoo answers are never that reliable. Okay so is it possible for masturbation or sex or anything that ends with an orgasm cause menstruation to happen sooner? Because my period started in the middle of having sex. I am curious if this is a thing that happens or if it is a fluke? I read that the orgasm causes micro contractions of the uterus and they are the same as the contractions that cause the tissue to come out, just that one is pleasurable and one isn t. Is that true?