I'm due September 15th and my next us is April 25th to find out the gender :)
you should be about 18 weeks at your next u/s so as long as baby cooperates you should be able to find out for sure, im due the 17th of september and going for my scan april 30th to find out :)
I'm due 9/15/14 and measuring 2 days ahead! I won't find out the gender until 4/29/14! It's such a long wait!