My Dr told me 8-12Kg is the average aimable weight gain if you're a healthy weight before falling pregnant. I of course, put on 19!!!! And I was not eating unhealthily - just hormones!! Everyone's different - as long as your baby is growing, your Dr isn't concerned, and you're not eating junk, don't worry about putting on too little or much. You can kick the extra weight after you've had the baby. Some women will only put weight on their tummies and boobs, and some this will all be baby, but others will pad out all over or in hormonal spots like the bum and thighs. It's very individual.