Normal Heart rates?

When I went to my first U/S at 9 weeks the babys heartrate was 170 then when I returned for the 13week First Tri Screening U/S it was 136...Is it normal for it to drop so much within a few weeks? Im sure im just being a worry wart cause I have lost 2 babies but I was just wondering if this has happened to anyone else?

My son's has ranged between 127-167 bpm. I'm sure everything is fine. (:

They would have told you if they were concerned. my son's heart rate at 35 weeks will be in the 130's one week and be 170's another week and they have never expressed any reason for concern i'm sure it's fine.

As long as its high like that its fine....

Normal. My daughtes would go from 120-170.

maybe the baby was sleeping

It's normal. The heart rate usually peaks at 9-10 weeks and then settles into a slower rhythm. Things like activity level of your baby can effect the reading too. My daughter has been as high as 190 at 9 weeks to as low as 130 at 12 weeks. She usually is around 140 now.

Thank you everyone, I feel better after reading some of those