The first endo I went to turned me down but the reasons she gave, including my age, were invalid. And a friend of mine who is a nurse said that endo was cherry picking easy to manage cases...young trans people. The second endo I went to has worked with over 4000 transgender people and he said he saw no reason I shouldn't start HRT. So it does happen but I don't see why sleep patterns would have anything to do with it.