When your period starts at an inconvenient time, it can be frustrating. It's especially difficult for teens whose life schedule and periods don't quite sync up. But there are ways to make your period start sooner reddit, like drinking lots of orange juice. This is because Vitamin C can reduce the levels of progesterone in the body, encouraging uterine lining shedding. And having sex or masturbating can also trigger menstrual contractions, which can help your period come faster.