How much weight will I gain during pregnancy?

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A row of pregnant women with different body shapes and belly sizes kneel on the grass.

A row of pregnant women with different body shapes and belly sizes kneel on the grass.

Pregnancy is an exciting time, whether you’re carrying your first baby or bringing a new member into a larger family. But there are elements of pregnancy that can cause some women concern, including weight gain. Are you gaining enough weight, have you put on too much, how will you lose the weight once you’ve given birth?

Gaining a healthy amount of weight is an important part of keeping you and your baby healthy during pregnancy and after birth. A worldwide study showed that about three out of four women weren’t gaining healthy amounts of weight while pregnant, with nearly a quarter of women not gaining enough weight, and almost half gaining more than a healthy amount of weight.

Read on to find out how much weight you should expect to gain during pregnancy, and diet and exercise tips to help keep you and bub healthy during pregnancy and after birth.

What’s a healthy weight?

How much weight you should gain while pregnant will depend on your pre-pregnancy weight and your pregnancy (if you’re carrying triplets, expect to see those scales rise a little more!).

Most of us have heard of ‘body mass index’ or BMI – a tool used to determine if you are underweight, have a healthy weight or are overweight. Your BMI is a number and gives an idea of how much weight you’re carrying across your frame by dividing your weight by your height. A healthy BMI is between 18.5 and 24.9. You can calculate your BMI using the Health Direct calculator.

Based on your BMI from before you fell pregnant, your health professional can advise you about recommended weight gain during pregnancy.

If you were in the healthy weight range before becoming pregnant, then ideally you should gain between 11.5 and 16 kilograms during your pregnancy. You should expect to gain 1–1.5 kilograms in the first three months, then 1.5–2 kilograms each month until you give birth.

If you’re overweight or underweight, the goal posts will shift a little. Women with a low BMI (under 18.5) should gain between 12.5 and 18 kilograms throughout their pregnancy. Women with a higher BMI (above 25) should gain between 7 and 11.5 kilograms.

Talk to your doctor and use a tool like the Pregnancy Weight Gain Charts linked below to map out how much weight you should expect to gain each month of pregnancy.

Pregnancy Weight Gain Chart for women with a BMI below 25. (PDF)

Pregnancy Weight Gain Chart for women with a BMI above 25 (PDF)

Why worry about weight?

Being underweight or overweight during pregnancy can have an impact on your health and bub’s health.

Being underweight can increase the risk of low birth weight for your baby and preterm (early) birth.

Gaining too much weight while pregnant can increase both short-term and long-term health risks for you and your baby, including:

  • gestational diabetes during pregnancy
  • type 2 diabetes after pregnancy
  • pre-eclampsia
  • depression
  • difficulties during birth
  • miscarriage or stillbirth
  • large for gestational age baby
  • requiring caesarean birth
  • later life obesity and metabolic syndrome for baby
  • and shorter duration or no breastfeeding.

A group of pregnant women sit in an antenatal class, discussing pregnancy with their teacher.

What can expectant mothers do to achieve healthy weight gain?

Pregnancy is a great time to develop or maintain healthy eating habits. Healthy eating will keep you feeling good and give your baby the essential nutrients they need. Overall, aim for a balanced diet, with a wide variety of nutritious foods. The Australian Dietary Guidelines booklet ‘Healthy eating during your pregnancy – advice on eating for you and your baby’ (PDF 2.23MB) provides a guide for expectant mothers.

If you’ve got questions about how you should eat while pregnant, speak with your doctor, who can guide your diet or refer you to a dietitian. You can also read more about pregnancy dietary and supplementation requirements in Queensland Health’s Maternal and infant nutrition guidelines and in our blogs 'Is it true I can eat for two while pregnant?' and 'What supplements should I take during pregnancy?'.

Exercise is also important while you’re pregnant. You should aim for 30 minutes of physical activity on most days of the week. Keep in mind that you can split these 30 minutes over the day – three, 10-minute walks can replace a 30-minute stroll on a busy day.

Exercises like walking, swimming and light aerobic classes are all suitable while you are pregnant. Aim for moderate exercise, which means you could still talk normally during your workout, but couldn’t sing. You can find more exercise suggestions for pregnant women on Pregnancy Birth Baby. Talk to your doctor about what types and intensities of exercise will be best for you throughout your pregnancy.