I think I gained around 4kg by 22 weeks but i also had and still have awful nausea and Vomiting. So I lost a bit of weight in the first trimester then put it back on.

I'm 35 weeks now and have gained 9kg. But like previous poster have said everyone is different, my BFF gained 20kg all up her last preg, I don't think I'll tip the 10kg mark this time.