<iframe width="426" height="240" src="https://www.youtube.com/embed/9Q44W0_-jSU?autoplay=1&controls=0&loop=1&rel=0&showinfo=0&color=white&playlist=9Q44W0_-jSU"></iframe>
https://productforums.google.com/forum/#!msg/youtube-es/ncLDGg4wKfE/Ao9KPEjwAwAJ
https://developers.google.com/youtube/player_parameters#loop