But increasingly, there is a new concern.
It is estimated about half of Australian women are entering pregnancy overweight or obese, with many putting on excessive weight while pregnant.
Jane Raymond, manager of Maternity and Newborn in NSW Health, said weight gain tends to be cumulative and lasting during child-bearing years..
"Pregnancy now is called an independent risk factor for obesity," Ms Raymond said.
Increasingly, research is linking a pregnant mum's weight to the health of her child.