Hi. I'm almost 30 weeks pregnant & I had 2 NST's 2 days n a row. Baby's heart rate was mainly around 140-150 but I seen it drop down into the 40's multiple times then go right back up seconds later. I also had an ultrasound & my fluid levels are good. So are these large but quick dips in my baby's heart rate normal?

Sometimes baby moves out of range of the monitor, and belt gets readjusted... sometimes it is an actual deceleration (or rise in some cases). You will commonly see the deceleration... when, and for how long, it occurs can give an idea as to what is normal, or if further evaluation is needed. If they didn't mention any concern, or the need to check further, sounds as though all is well.