Pregnancy weight gain calculator
How much weight to gain depends on your BMI before pregnancy. Women with a healthy BMI usually gain 11.5 to 16 kg (25 to 35 lb) in total, mostly after the first trimester. Enter your details to see your range and what's typical for your week.
Recommended weight gain by BMI
| BMI before pregnancy | Total gain (one baby) | Weekly, from 2nd trimester | Total gain (twins) |
|---|---|---|---|
| Under 18.5 (underweight) | 12.5 to 18 kg (28 to 40 lb) | 0.44 to 0.58 kg | Ask your doctor |
| 18.5 to 24.9 (healthy) | 11.5 to 16 kg (25 to 35 lb) | 0.35 to 0.50 kg | 17 to 25 kg (37 to 54 lb) |
| 25 to 29.9 (overweight) | 7 to 11.5 kg (15 to 25 lb) | 0.23 to 0.33 kg | 14 to 23 kg (31 to 50 lb) |
| 30 or more (obese) | 5 to 9 kg (11 to 20 lb) | 0.17 to 0.27 kg | 11 to 19 kg (25 to 42 lb) |
Source: US Institute of Medicine (now National Academy of Medicine), 2009. These ranges are widely used around the world.
A note for South Asian and Middle Eastern women
Research shows that people of South Asian, Middle Eastern and East Asian background face higher risks of diabetes and heart disease at a lower BMI. Many doctors in these regions treat a BMI of 23 or more as overweight and 27.5 or more as obese. If your BMI is near a boundary, ask your doctor which range applies to you. Gestational diabetes is also more common in these groups, so read about the glucose test.
Gaining weight healthily
Eat regular meals built around vegetables, pulses such as daal and chana, wholegrains, dairy and lean protein. Limit sweets, sugary drinks, fried snacks and large portions of rice and naan. Stay active with 150 minutes a week of moderate activity, such as walking or swimming, if your doctor agrees. Read our pregnancy weight gain guide for more.
Weight gain questions
How much weight should I gain in pregnancy?
It depends on your BMI before pregnancy. With a healthy BMI (18.5 to 24.9), aim for 11.5 to 16 kg (25 to 35 lb). If you were underweight, 12.5 to 18 kg; overweight, 7 to 11.5 kg; obese, 5 to 9 kg. With twins the ranges are higher.
How much weight should I gain in the first trimester?
Usually only 0.5 to 2 kg (1 to 4.5 lb). Many women gain little or even lose a bit because of morning sickness. Most weight is gained in the second and third trimesters.
Do I need to eat for two?
No. You need no extra calories in the first trimester, and only about 200 to 450 extra calories a day later in pregnancy, depending on which guideline you follow. That's roughly a bowl of yoghurt with fruit or a sandwich.
Where does pregnancy weight go?
At full term, a typical gain includes the baby (about 3.4 kg), placenta (0.7 kg), amniotic fluid (0.8 kg), a bigger womb (1 kg), more blood and fluid (about 3 kg), breast growth (0.5 kg) and fat stores for breastfeeding (about 3 kg).
Should I diet if I'm gaining too much?
No. Don't try to lose weight during pregnancy unless your doctor advises it. Focus on balanced meals, fewer sugary drinks and fried snacks, and regular activity such as walking. Your doctor can refer you to a dietitian.