I went for an ultrasound last Friday at what I thought was 7w1d. It was a transvaginal ultrasound so I was sure I would see the baby. Well, the tech told me that my uterus is VERY VERY tipped and they were only able to find the yolk sac. I'm going back on this Friday so we can try to see the baby, but I was assured that a tipped uterus makes it very difficult to see anything until the uterus corrects itself. I've read that some may not hear the heartbeat with the doppler until 13-14 weeks, and even with an ultrasound it is sometimes hard to identify the baby until then.