I'm not one to believe that stress prevents pregnancy.
Women get pregnant after rape, during famine, at times of war, etc.
My first child was conceived at my 4th IUI. I was VERY stressed and convinced that it wouldn't work. Within 2 days prior to the IUI, my grandfather passed away. It was devastating. I was crying all the time. And I still got pregnant. In fact, the first entire year was pretty stress free. So why didn't I conceive then?
So, no, I don't think stress is keeping you from getting pregnant. I wish I could tell you what was the problem though.
I find that with unexplained infertility, we start to blame ourselves and we grasp at straws to try to fix things, "Hey, if I relax, eat pineapple, exercise more or less, have sex just for fun, use preseed, take extra folic acid, have sex doggie style, etc..... I will get pregnant."
Honestly, I don't really think any of it matters. It all comes down to luck.
But, I also just keep trying new things. I've tried different bd timings, and positions. I've tried temping and bloodwork. I've tried meds and IUI. Nothing has worked. Trying to be less stressed, well it's worth a shot.
I just have to say that it bothers me a little bit when I hear of women that are taking the responsiblity of infertility on themselves, due to stress.
Give yourself a little break.......it's not your fault.