Above except for obese weight gain is from Subcommittee on Nutritional
Status and Weight Gain during Pregnancy and Subcommittee on Dietary
Intake and Nutrient Supplement during Pregnancy, Food and Nutrition
Board, National Academy of Sciences: Nutrition During Pregnancy, Parts I
and II. Washington, D.C. National Academy Press. 1990.
The obese weight gain recommendation is from Krause's Food, Nutrition,
and Diet Therapy by L. Kathleen Mahan and Sylvia Escot-Strump; 9th
Edition (1996), pp. 183-184.
Below are the values used to define the different weight for length and
age categories.
| Categories for length and age: | |
| Under weight (CDC) |
less than 10th percentile |
| Under weight |
less than or equal to the 10th percentile |
| Normal weight |
greater than 10th to less than 95th percentile |
| At risk of over weight |
85th to less than 95th percentile |
| Over weight |
equal to or greater than 95th percentile |
| Biological implausible values |
z-scores less than -4 or greater than 5 |
*Although the 1998 National Heart, Lung and Blood Institute (NHLBI)
Clinical Guidelines on the Identification, Evaluation and Treatment of
Overweight and Obesity in Adults define adult obesity as equal to or
greater than 30 BMI; the Institute of Medicine (1990) recommends using
the pre-pregnancy weight classification that
defines obese prenatal women as > 29.0 BMI, for postpartum, lactating and
non-lactating women.