Weight gain in pregnancy
There should be no large weight gain during the first trimester of pregnancy.
- About 45% of total pregnancy weight gain happens in weeks 26-32
- A further 20% occurs during weeks 32-40
NICE (National Institute for Health and Clinical Excellence) is in the process of developing guidelines on weight gained during pregnancy but this is not expected until Jan 2010.
Pregnancy weight gain
The amount of weight gain with the best pregnancy outcomes depends upon the mother’s weight at the beginning of pregnancy.
- The Body Mass Index or BMI is a useful measure
- BMI = weight(kg)/(height(m)2)
- BMI of 24 is associated with the optimum pregnancy outcome
| Pre-pregnancy BMI |
Optimum Pregnancy weight gain (kg) |
| <19.8 |
12.5 - 18.0 (27 - 40lb) |
| 19.8 - 26.0 |
11.5 - 16.0 (25 - 35lb) |
| 26 - 29 |
7.0 - 11.5 (15 - 25lb) |
| >29 |
6.0 (13lb) |
Table Reference:
Institute of Medicine; Nutrition During Pregnancy (1990) Part 1: Weight Gain, p5
http://www.nap.edu/openbook.php?record_id=1451&page=5
Dieting during pregnancy
Slimming diets during pregnancy are not recommended.
- Weight loss is associated with a poor pregnancy outcome
- Restriction of calories can result in a shortfall of many nutrients
- Recommend an unrestricted but healthy diet rich in fruit, vegetables and wholegrain cereals
- Substitute high-fat foods for lower fat varieties
- Individual dietary counselling may help women manage weight gain during their pregnancy