Does anybody know what causes ageing ovaries?

That is crazy! I know we are all supposed to be born with about the same amount, but each month utilize more than one egg. Your ovaries start production on a bunch of follicles, just a winning one comes out! Maybe women with aged ovaries have like an overactive amount of Follicle Stimulating Hormone and they work overtime. I think that Estrogen and Progesterone are produced from the ovaries, so maybe they have high hormonal amounts. I am sure it is just not known. Just like the women who have early menopause, at like 21. One of those weird "flukes". I can't see how alcohol or drugs would do that to your ovaries. The female reproductive system is just the most technical thing, there are a like a million things that can go wrong. Wonder if they've done any research studies on this? Interesting...