I pass a lot of clots every month when I bleed. It's been happening for years, sometimes worse or slightly better. I recall one year when it was utterly unbelievable---having to sit on a towel in the car, and even then, bleeding all over the place... I feel for you, I really do.
One of the bigger problems associated with this extra-heavy bleeding is anemia. Over the years, from losing so much blood, I became extremely anemic. A few years ago I hit bottom with that, and my condition was so severe that a naturopath recommended a blood transfusion! The solution to that involves taking iron and making dietary changes I guess. I've gotten better with regard to my iron levels...
Yet, the clots keep coming. I went back on the pill for a year. That cuts down on the bleeding a lot, though it's probably not a good idea to take artificial hormones like that---but I was feeling desperate. As far as natural solutions go, I just read another post in this forum recommending a certain "female formula" product, and after checking out its ingredient list I recalled how Chaste Tree Berry (also known as "Vitex") once worked wonders for me. Prescribed also to me by a naturopath, I took it for a while and it quickly reduced the bleeding to what I would consider a normal acceptable level. However, it started making me nauseous then, and I stopped taking it. Now, being reminded about it, I'm going to take it again. Time has a way of changing things, so I'm hoping I won't have any trouble with it. And that's not to say that anyone else would get nauseous from it---I don't know if that's a common reaction, but probably more of a personal thing.
Anyway, you might want to give it a try. I don't much care for doctors either, especially allopathic GYN doctors---I've asked many over the years about these very concerns and gotten absolutely NO HELP from them whatsoever. They'd say "everyone's different, and there is a whole spectrum of what "normal" flow is. Sure, true, but you and I know that passing many large clots is nerve-wracking and cannot be good...
I wish you good health and peace of mind, my friend. If there is a way for you to check out your blood for anemia, I'd highly recommend that--perhaps a cheap clinic or something? Anemia has robbed me of vital energy for years, and it takes years to rebuild the red blood cell army with vitamins.