My last ultrasound was with my fertility specialist, at 10 weeks which she then transferred me to my regular OB. I saw my OB for the 1st time today at 14w 2d and we heard heartbeats! They were 161 & 163. The one thing I am upset about is she will not do another ultrasound until 18 weeks. Is this strange to go 8 weeks between ultrasounds for twins? She said they would be every 4 weeks after that..