A new guideline from the Institute of Medicine (IOM) emphasizes that physicians should advise patients on the appropriate amount of weight gain during pregnancy. It also tweaks previous recommendations for pregnancy weight gain to account for greater numbers of mothers who are obese or pregnant with twins.
The target ranges for weight gain for underweight, normal weight, and overweight women set by the organization in 1990 remain unchanged in the new guideline. However, the document's body mass index (BMI) ranges for each weight category were slightly changed to conform to those used by the World Health Organization rather than those derived from the Metropolitan Life Insurance tables used for the previous guideline.
Kuehn BM. Guideline for Pregnancy Weight Gain Offers Targets for Obese Women. JAMA. 2009;302(3):241-242. doi:10.1001/jama.2009.964