Growth scans

Deb
Anyone had growth scans where baby weight gain was rapid. This is my worst fear due to 2 previous pph. My previous babies have all apart from my little one been average 50th centile babies all the way through. I'm having a girl and thought good as she will likely be smaller than my boys. First scan 20 weeks 11oz so an average baby. Fast forward 20 days she's now 1lb 5oz that's double her last weight. Her legs are also very long. Has anyone had this and weight gain slowed. Next scan in 5 weeks. Just really don't want a 10lb baby due to it increasing my chance of serious bleeding. I know baby's have growth spurts but would be reassuring to hear the weight gain slowed.