Weight gain is closely monitored throughout pregnancy. How many kilos per month can you gain when you are pregnant? From what month do we grow? Answers and advice from experts.
There weight gain during pregnancy concerns many pregnant women, and health professionals who closely monitor the evolution of the weight of the future mother. Over the months of pregnancy, the mother-to-be will gain weight, for the proper development of the foetus. It is an important parameter to monitor during pregnancy, but also before becoming pregnant. Indeed, in women, weight also has an impact on fertility. In women with diabetes or other pathologies, for example, the weight will be monitored more during pregnancy. “The weight still remains a very limited risk factor unlike others”, explains Pr Philippe Deruelle, gynecologist-obstetrician. In any case, during your various pregnancy medical examinations, the practitioner who follows you will carefully note your weight and the number of kilos gained. The point and the advice of our experts.
Why do you gain weight while pregnant?
Weight gain during pregnancy is related to the development of the fetus in the womb, the weight of the placenta, the umbilical cord, the membranes and the amniotic fluid. But it is also due to the normal increase in maternal blood volume, breast and uterus, and sometimes water retention. Calories are also ingested differently during pregnancy.
When does weight gain during pregnancy start?
The pregnant woman can start gaining weight very early, “from the first trimester of pregnancy“. “At the start of pregnancy, the fetus has very little fat in utero. But fat is a source of energy for him. Pregnancy hormones will promote weight gain and fat storage, which will provide the fetus with sufficient energy without it being dependent on its mother’s diet. details the gynecologist.
What is the average weight gain during pregnancy?
There weight gain during pregnancy varies from woman to woman. It depends on different criteria, particularly in terms of health, according to the BMI (Body Mass Index).
- The Institute Of Medicine (USA) of 2009 recommends weight gain between 11 and 16 kilos for a woman of normal weight. “More generally, it is said that weight gain should be adapted to pre-pregnancy weight, i.e. according to the woman’s BMI”, emphasizes Professor Deruelle.
- In the case of’a type 1 obese woman For example, “instead we recommend a weight gain of 5 to 9 kilos.”
- “For an extremely obese woman, weight gain must be very limited, between 0 and 5 kilos“adds the specialist, taking up a recent study published in the scientific journal JAMA.
- Are you pregnant with twins? On average, weight gain between 12 and 16 kg is considered “normal”. However, discuss this with your doctor.
| BMI value before pregnancy | Recommended weight gain | Recommended weight gain per week in the 2nd and 3rd trimester of pregnancy |
| < 18.5 (thinness) | Between 12.7 kg and 18.1 kg | Between 0.45 and 0.60 kg per week |
| 18.5-24.9 (normal) | Between 11.3 kg and 15.9 kg | Between 0.36 and 0.45 kg per week |
| 25-29.9 (overweight) | Between 6.8 kg and 11.3 kg | Between 0.22 and 0.32 kg per week |
| > 30 (obesity) | Between 5 kg and 9 kg | Between 0.18 and 0.27 kg per week |
Latest official recommendations from the Institute of Medicine (2009).
How much weight gain during pregnancy month by month?
Weight gain in pregnant women should be as regular as possible and gradually increase until you give birth. But above all, it all depends on your pre-pregnancy weight. Do not hesitate to raise this subject during your first appointment with your doctor or midwife.
- During the first trimester of pregnancy, it is advisable to gain between 0 and 1 kg per month.
- For the second trimester of pregnancywomen with a normal BMI (between 18.5 and 25), therefore excluding overweight, thinness or obesity) can take jup to 1.5 kg per month.
- At third trimester of pregnancy, the baby’s needs are greater, a weight gain of about 2 kg per month maybe normal.
| month of pregnancy | Number of “allowed” kilos on average (for a woman with a normal BMI) |
|---|---|
| 1st month | max 1kg |
| 2nd month | max 1kg |
| 3rd month | max 1kg |
| 4th month | 1.5 kg maximum |
| 5th month | 1.5 kg maximum |
| 6th month | 1.5 kg maximum |
| 7th month | max 2kg |
| 8th month | max 2kg |
Calculating your weight gain during pregnancy in advance is difficult. “It’s very difficult to predict, because some women will react strongly to pregnancy hormones, even if they eat normally they will, for example, suddenly gain a lot of weight. And other women will, on the contrary, not gain more weight than that”, says Professor Philippe Deruelle. On the other hand, they can rely on estimates of recommended weight gain month by month, based on their starting BMI. But again, this varies greatly from woman to woman. Calculate your BMI with our calculator.
In which month of pregnancy do you gain the most weight?
There is no specific month during pregnancy when a woman gains the most weight. Again, this varies greatly from person to person. On the other hand, it is common to see women gain more weight towards the end of pregnancy, around the 7th and 8th month of pregnancy. “Women can gain more weight because they have more edema at the end of pregnancy, due to the pressure of the baby on the uterus which will compress the lower body”, reveals the gynecologist.
What are the risks of weight gain in pregnant women?
In case of excessive weight gain during pregnancy
Significant weight gain usually results in Gestational Diabetes, and even the risk of cardiovascular disease. The baby, meanwhile, is at risk of being born in overweight (big baby syndrome, 4 kilos and more), in case of gestational diabetes. It happens then that deliveries are triggered before term, by caesarean section, also with a risk of strangulation with the umbilical cord. But this is rare because pregnant women are now closely monitored by their gynecologist and sometimes even by nutritionists.
In case of too little weight gain during pregnancy
Below 5 kilos gained during pregnancy, there are more premature babies, smaller babies at birth and long-term chronic health problems. Women who do not gain enough weight are at risk of deficiency. Indeed, the baby will draw on the reserves of the mother. This one can for example have dental problems if it lacks calcium.
Our tips to avoid gaining too many pounds while pregnant
Want strawberries, chocolate or ice cream? If pregnancy can make you want to succumb to many gourmet temptations, it is not necessarily wise to always give in to them. The right reflexes to avoid gaining too much weight during pregnancy.
- Eat twice as good. “As the energy needs of pregnant women are the same as in normal times, except at the end of pregnancy, when they are increased by 100 to 200 calories, the main thing is not to eat twice as much, but twice as good !”, advises Florence Pujol, nutritionist.
- Eat when you are (really) hungry. “The most important thing for future mothers: learning to eat when you feel the need and stop if you are no longer hungry, even if you have not finished your plate. Then, to avoid so-called “overconsumption” weight gain while maintaining a balanced diet, force yourself to eat slowly by putting the fork down after every three bites, so that the body has time to express its satiety to the brain. Also be sure to make smaller pieces,” recommends Florence Pujol.
- Avoid snacking. In case of cravings, you can split meals, but without add ! This will save you from snacking, often made of sweets and other high-calorie foods.
- What about cereal bars? The dietitian advises against them. For what ? They contain fast sugars which promote the production of insulin, and therefore weight gain. She recommends consuming “healthier snacks such as dairy (yogurt, cottage cheese), a slice of bread with a little butter to slow down the digestion of the carbohydrates contained in the bread, a compote with no added sugar, fruit with or without cottage cheese, etc.“
Can you diet during pregnancy?
Dieting during pregnancy is not recommended. “Restricted babies during pregnancy have a greater risk, as adults, of developing diabetes or obesity, for example. For the mother, the risk is relatively limited if she has no major deficiency. Less than one weight loss during pregnancy (which can happen in women who have undergone bariatric surgery for example) which can lead to vitamin deficiencies, there are few very dangerous effects. What may emerge, however, is a lack of energy to push during childbirth and difficulty breastfeeding.“, warns Dr. Deruelle.
- For someone with a low BMI, “a diet would be dangerous, with risks of undernutrition, fetal developmental disorders, and even loss of the baby, in the worst case” completes nutritionist Florence Pujol.
- For a person with a normal BMI, a personalized ‘food rebalancing’, established beforehand with a specialist, does not present any risk.
- Finally, for a woman with a large BMI, “only this balanced diet can be enough for a weight loss of 3 kg at the start of pregnancy and a minimized weight gain thereafter.”
Source: American Institute of Medicine. Weight Gain During Pregnancy: Reexamining the Guidelines. 2009 May.
Association of Gestational Weight Gain With Adverse Maternal and Infant Outcomes. 2019 May
Thank you to Pr Philippe Deruelle, obstetrician gynecologist at the University Hospital of Strasbourg, to Béatrice Benavent-Marco, dietitian nutritionist and to Florence Pujol dietitian nutritionist and behaviorist in Paris.