Because lots of weird shit happens to women. Pregnant or not? Maybe your hormones aren't right - one of the signs is usually change in monthly cycle. Whenever

Because lots of weird shit happens to women. Pregnant or not? Maybe your hormones aren't right - one of the signs is usually change in monthly cycle. Whenever you have to go to the doctor for pap smears and so on, the doctor asks about it. For some folks, their weight determines their cycle length - too much or too little fat can change fertility. Perhaps you get really, really bad PMS (PMDD) and need to take anti-depressants around 2 weeks before the beginning of your cycle. And more, I'm guessing. I just can't think of another example right now, but in any case, monthly cycles are a big indicator of health issues and can be a great help with life issues as well.