Pregnancy is the only stage in your life when weight gain seems natural. However excessive weight gain even during pregnancy isn t a good idea. The reason being too much weight can give rise to complications that can come in the way of a smooth labour. Nevertheless weight gain during pregnancy is vital and necessary. It is also an important parameter that reveals a healthy development of the baby. How much weight should one gain? Weight gain during pregnancy should be consistent and gradual. Nobody knows exactly how many kilograms a pregnant woman should gain as it is very subjective.