I found out via ultrasound on October 28th that I am pregnant with identical twins (in the same sack). On 10/28, the larger twin (twin A) was measuring 5 weeks 6 days with a faint heartbeat. Twin B was smaller (I don't know how much smaller), and no heartbeat was detectable. 5 days later, on November 2, I had a follow-up ultrasound b/c of bleeding. Twin A is now measuring 7 weeks 4 days, and twin B is measuring between 5 weeks 6 days and 6 weeks 1 day. No heartbeat for twin B yet.