Researchers from the Harvard Medical School looked at the pregnancy guidelines issued in 1990 by the Institute of Medicine, a private non-governmental organization that advises the federal government, and reported that the standards about how much weight a woman should put on during pregnancy may need to change.

New study results suggested that the accepted weight gains may not be appropriate and may raise the risk of having an overweight toddler.
Women in the study who gained the recommended amount of weight had four times bigger risk of having a child who was overweight at age 3 comparing to women who gained less than the advised amount.

It is still not clear what a pregnant woman is supposed to do. One thing is certain, she should not gain more weight than recommended.
However, it may still be early to say whether women should try to gain less than the standards call for or shoot for the low end of the recommended range.

The current guidelines recommend different amounts of weight gain depending on how much a woman weighed before pregnancy. Women with normal BMI are encouraged to gain between 25 to 35 pounds while those women with higher BMI should gain less weight and those with lower BMI, more weight.

The study author said they are not certain why greater weight gain in the mother would raise the risk of her toddler becoming overweight. It is known that women who have diabetes during pregnancy usually have bigger babies who run a heightened risk of obesity later in life. This knowing may suggests a factor in the womb that could be affecting a baby's future.

Gaining too much weight carries risk for the mother’s health as well as difficult delivery or Caesarean section. On the other hand, gaining too little weight poses a risk of having a low-birth weight baby.

The conclusion is that women need to balance. They should better aim for the lower end of their recommended weight gains for their own well-being as well as the well-being of their child.