iui twins gender ?

Brittney
I had an <a href="https://glowing.com/glow-fertility-program">iui</a> done and got pregnant with my twins. Had a sono yesterday at 16.5 weeks. They gave us the genders of both. Looks like we're having two girls! I've read that scans a lil early may not be 100 bc girls can sometimes get mixed up bc of swelling. Should i trust the tech that she was confident that she knew they were girls?? I wanted to do a gender reveal for Christmas season, but I wanna be more sure. Thoughts???