I posted a question a few days ago about my doctor hearing two heartbeats at my last appt. Well, I had my 16 week check-up today (I won't get an ultrasound until my next appt. at 20 weeks) and there was a nice strong heartbeat on my lower left side and she moved it to the right side and there was another strong heartbeat over there. Both heartbeats were in the 150's so she assumed that it's just one baby and she is picking up the same heartbeat on both sides. It was very interesting though because she moved it back and forth a few times and would find the separate heartbeats. I'm not measuring bigger or anything and I've gained about 5 lbs. so far. What do you think? Thanks!