Ultrasound / heart rate to guess gender

Heather
I had my u/s yesterday at 8w2d. Heart rate was 180. From what I read, higher heart rates like that tend to mean it's a girl. From the start I've had this gut feeling it's a gir. Anyone else ?
All but 1 of the Chinese gender charts say girl. That Ramzi or whatever it's called theory would say boy though. Lol I guess only time will tell