HAIR LOSS - CAN IT BE BECAUSE OF HORMONE IMBALANCE?

I've been struggling with my hair for a while now. It's always been thin, but the last 2 or 3 years it's become thiner and it's been falling a lot. It takes SO LONG to grow. My haircuts usually last for months and months because my hair won't grow normally. I've tried several products and vitamins, but nothing seems to make a big difference. Do you girls think that maybe there's a health issue related to all that? Hormonal imbalance maybe? What do you know/think?