I'm 32 weeks along with number 3 (9 yr gap between youngest and baby) and had my third trimester scan today baby is growing nicely but with my older 2 their heart rates always stayed the same through with only minute changes. This ones heart rate had always been around 159-162 until about 3 weeks ago when changed to between 132-137. The sonogragher says its normal. Has anyone else had this happen? Also baby's gender is unknown