It's not true: women with retroverted uteruses get pregnant all the time -- it will right its position during the pregnancy, too.
I have one, my mother has one, and she had 3 kids and I'm 12 weeks with my second.
Good luck!
I had endometriosis of my uterus (corrected by surgery) and have a retroverted uterus and am 13 weeks pregnant with my first bub. I fell pregnant very easily so I'm sure you will have no trouble! Good luck.
I have endo and conceived naturally and first time. My mum had a retro erred uterus, was told shed have trouble and had 3 natural, easy pregnancies. My girlfriend with endo had a laproscopy to remove all possible endo and then immediately fell preg by IUI, another by IVF. So its possible! I'm not sure about your combination though.
Good luck!