Heart Rates

Had an ultrasound yesterday at 9w4d and the baby’s HR was 152. At 6w4d is was 122. I know those numbers are within normal limits, but it seems like they are a bit lower than what most people are reporting their babies’ heart rates to be at those times. Seems like a lot of babies’ HR have been 170+?

With my daughter (first pregnancy), I honestly don’t remember what hers were, but I don’t remember worrying that they were on the lower side of normal like I have been with this one.

Anyone have similar heart rates to mine?

Also, this is a rainbow baby, I had a MMC at about 5 or 6 weeks in October of 2018 (never has a heart beat), so I’m extra sensitive/on edge...