Dr Rahul Sen | Specialist care for birth and beyond | Sydney, Australia

Rooms : Edgecliff 02 9363 9474
Macquarie Street 02 9221 2600

Weight Gain in Pregnancy

Healthy Weight Gain in Pregnancy by Natasha Leader

Most women should gain between 10 and 15 kg during the pregnancy. About half of that is from the baby, the amniotic fluid, the placenta and the womb. The other half is extra fat stores, blood and other fluids and breast development. If you gain too much or too little weight it may affect the pregnancy.  If you gain more than 15 kg it may be difficult to lose the weight afterwards.

Your ideal weight gain depends on your starting weight or body mass index (BMI), which is your weight in kilograms, divided by your height in metres multiplied by itself (weight/height2):

Weight status BMI Ideal Total
Weight Gain
Underweight < 18.9 12.5 – 18 kg
Normal Weight 19 – 24.9 10 – 15 kg
Overweight 25 – 29.9 7 – 11 kg
Obese 30 – 34.9 3 – 7 kg
Morbidly obese > 35 0 – 4 kg

Watch your weight gain

Everyone is different and weight gain will always vary between women but it is important to keep an eye on it.  A higher weight gain can lead to complications that are potentially avoidable.  In the women I regularly see who have gained an excess amount of weight, a diet history usually reveals the culprits are high calorie snacks and bigger portions at meals.  Portion size is a vital part of weight management.

If you are hungrier and are already eating the recommended amounts of protein/starch already then the best way you can bulk out a meal is by adding vegetables – while the other meal components may be nutritious, if you’re overdoing it you’re more likely to put on too much weight.  A quick way to think about it is by using the ‘plate’ model.  Half your plate should be salad or cooked vegetables, then a quarter lean protein (meat/chicken/fish/tofu/eggs), and a quarter starch (bread/rice/pasta/quinoa or noodles).

My five top tips

  1. Choose high fibre breads and cereals
  2. Choose low fat dairy products
  3. Choose lean meats
  4. Eat more vegetables
  5. Choose your snacks wisely

It’s all in the planning

If you are feeling sick often the last thing you feel like doing is thinking or talking about food but spending a short time focusing on your shopping list and planning ahead will help a lot in managing your diet.  Ensuring you have nutritious snacks on hand and a list of options for work lunches as well as perhaps some weekend cooking to enable quick but healthy dinners through the week will save you from the trap of banana bread, giant sandwiches and late night laksas!

It isn’t always easy but it is worthwhile

The potential changes to your appetite, nausea plus cravings and food aversions along with early fatigue make it a trying time for you – not to mention the food safety restrictions and conflicting information you might read.

I look forward to seeing all of you early on in your pregnancy, to work with you to answer any queries you may have.   I aim to provide some practical help in managing any of the above considerations, as well as looking at the adequacy and balance of your diet.  We can also focus on any planning, shopping, label reading and cooking issues you may have!


From Dr Rahul Sen…

I check your weight at your booking visit and then each month during the pregnancy.

I calculate your Body Mass Index (BMI) at booking.  BMI is your weight in kg divided by your height in metres divided by your height in metres again.  A normal BMI is 19-25

If your BMI is very low, your baby may not put on enough weight, so we may need to monitor the baby’s growth.

If your BMI is very high it is difficult to assess growth during pregnancy and fetal wellbeing during labour.  You may need extra ultrasound scans and extra monitoring during pregnancy.

Most women gain 10-14 kg during the pregnancy.  If you gain a lot more than that then there is an increase in risk of diabetes in pregnancy.  It is also much harder to lose the weight after the baby is born.

If your BMI is above 25 you should aim to restrict your weight gain as per the BMI table above:

The best way to control your weight in pregnancy is a regular, balanced diet, high in complex carbohydrates, fibre and protein, and low in sugars and fats, high volumes of water, and 20-30 minutes of planned, physical exercise per day, of at least moderate intensity.

If beneficial, I shall refer you to a dietitian during pregnancy.