First time round we didn't care, we didn't find out until baby (boy) was born. It was an amazing experience to find out on the day, an experience that still makes me emotional when I think about it now.
I did however feel very strongly that baby I was carrying was a boy, so much so that had I given birth to a girl I'd have been questioning my "mothers instinct" 
This time round OH expressed a strong wish to find out [he let me make the decision with our first] and we had other factors to consider. Finances were tighter, we had a new room to decorate etc.... After dating scan I agreed that we would find out and I must confess that my want for a daughter grew. It would have been so much easier to have a boy... We had all our boy clothes, the kids are sharing a room, we know what to do with a boy and we love having a little boy BUT I wanted a girl.
Anomaly scan showed I got my way and were were having a DD, literally 2 minutes after being told this we were then told that there was an issue with baby without going into too much detail worst case scenario was a life limiting illness.
Of course the health of my baby was paramount. It goes without saying but the amount of guilt I felt was horrific. I felt as though I'd spent so much time and effort concentrating on gender I'd somehow 'overlooked' the obvious.
Now of course we would love our child no matter what but at that moment if you'd ask me to choose a girl with possible life limiting illness or a healthy son I'd have opted for healthy. Because I want a child who will thrive, who will be fit and well, who will enjoy life and not suffer any pain.
(this is not in any way, shape or form meant to debate the pro's and con's of having a child with an illness / disability and the condition they suspected was never going to mean I'd even consider a termination. I refused an amnio as well)
I am just trying to put into words how my gender preference was completely overshadowed when it came to it.
As things turned out DD was fine. She is due anytime now and regular scans, assessments, genetic testing (on me and OH) have ruled out any issue.