As with many aspects of health and fitness the amount of weight gain during pregnancy will vary greatly from individual to individual. It depends on many factors; the amount you eat during pregnancy, existing lifestyle and work factors, activity levels but most importantly how much you weigh at the start of pregnancy.
Most pregnant women will gain between 10kg and 12.5kg during pregnancy, with most of this weight coming after week 20 (NHS UK). However if you are overweight at conception then weight gain is usually less.
This increased weight is mainly due to the baby growing, but you will also be storing more fat than usual and experiencing an increase in breast size as your body prepares to feed a new-born.
Weight gain timeframe
In general, you should gain at most about 1-2kg during the first three months you’re pregnant and 0.5kg a week during the rest of your pregnancy. This would be an average of 0.75kg per week after the usual weight gain in the first three months.
Weight gain breakdown
By the time you reach your due-date, around a third of your extra weight will come from the baby, the placenta and amniotic fluid. The other two thirds in weight comes from the changes that happen to you during pregnancy. On average the muscular layer of the womb increases by 0.9kg; blood volume increases and weighs an extra 1.2kg; fluid retention around the body comes to 1.2kg; breast size increase adds 0.4kg and extra fat stored for breast feeding is around 4kg.
Should I try to lose weight if I was overweight at conception?
If someone is very overweight at conception, their doctor may want them to lose some weight during pregnancy. However this would normally only be recommended for the first trimester and at a gentle rate of 0.5 to 1kg per week. The emphasis should be on healthy and varied foods, as with any healthy nutritional plan, with a good balance of macros (protein, carbohydrate and fats). For most people weight loss during pregnancy would not be recommended.
Beware eating for two
“Eating for two” is a myth, as we can see above from the conservative normal weight gain during pregnancy. So it’s important to not use pregnancy as an excuse to go crazy food-wise. It’s always so much easier to stay within the guidelines than to accelerate away from them during pregnancy. Those pounds will be difficult to lose after birth, especially with your changed hormonal balance. If we look at the average weight gain of 12kg and divide it up over the course of your pregnancy then you only actually need an extra 150 calories a day. Remembering that only up to 2 kg will go on in the first 3 months gives us a slightly more time accurate calorie increase of 80 calories a day above your BMR (basal metabolic rate) for 3 months then an extra 200 calories per day after that.
Use technology to stay on track
Modern technology is one of the best ways of keeping your weight gain healthy and on track. Smart phone apps can track every aspect of your pregnancy including weight gain. Digital scales can send daily weight data to your smart phone which can then produce a graph that will show where you are weight wise against a normal guideline. A popular and highly rated app is Pregnancy + but there are of course others.