My baby number 4 stopped growing just over half way thru my preg. She had hypopituitarism but it wasn't diagnosed until she was a few months old.
For those that don't know, its the pituitary gland not releasing hormones (in my child's case, no growth hormone) as well as not being fully formed, non communication with the brain, low thyroid etc.
As it couldn't be treated in the womb, I chose to increase my diet. Lots of organic food, homemade smoothies, pastas, rice, potatos, fruit, fresh veg, just lots of really good food.
They initially predicted a baby of 4lbs and below. They left her inside of me as they felt it the safer option. She was delivered several weeks early by c section weighing in at 6lbs 10oz.
Good luck x
Drink plenty of milk.get creative with it.chocolate milk, hot milk with a splash of hazelnut flavor, or your favorite creamer.it works my baby was 4 lbs at the end ofeight months.i did the milk thing and he was born 5lbs,11oz at 36 Weeks
Eat highly nutritious foods (not junk). Plenty of fluids. Regular mild - moderate exercise (unless it's contraindicated by your dr). It increases blood flow to you and also to the baby. Rest lying on your left side (this also increases blood flow to the baby).
Try not to stress too much about it all. The measurements are not that accurate.