Irregular Period

​My period decides to come whenever it wants to. I've even gone months with out having it! I'm not sexually active so I know that's not the reason it's not coming and I've even gone to the gynecologist and she said irregular periods are normal but I just want to know if anyone else had the same problem I have and what are they doing to prevent it? I thought about birth control but I'm very iffy on it because I always hear something bad about it and I don't want to put the weight on that I get from taking it. What should I do???