Weight gain during pregnancy - how much is healthy?

Exercise is still important in pregnancy.
Exercise is still important in pregnancy. Photo: Shutterstock

When it comes to managing your weight during pregnancy, the first step is to understand the recommendations for weight gain during pregnancy. Having the knowledge to know what to aim for in the beginning can only be beneficial. This will vary for everyone and should be individualised. As outlined in the table below there are guidelines for weight gain based on your starting BMI. There are also different guidelines for women with multiple pregnancies, such as twin pregnancies. These guidelines are used widely throughout Australia and New Zealand.

Myth Graph

Managing your weight during pregnancy will reduce you risk of developing medical complications such as gestational diabetes, gestational hypertension, pre-eclampsia and postpartum haemorrhage to name a few, some of which can have longer lasting consequences for you and your baby.

And remember, the amount of weight a woman might gain in pregnancy is only partially due to fat. There is also the baby, placenta, amniotic fluid, increased maternal blood and fluid volume.

Sorting fact from fiction

You do not have to "eat for two". This is a myth. Some women have read that they require certain amounts of nutrients for the growth of a healthy baby and they become far too focused on these numbers. Before they know it they've gained 12kg and they're only 26 weeks gestation.

You do not have to drink full fat milk. Energy requirements don't change in the first 6 months and then only slightly increase in the last 3 months (~ 200 calories/day).

My advice to women is to have a healthy diet and to avoid the few foods that are not recommended in pregnancy (eg. raw meat, eggs, soft cheese, alcohol, etc) but there is no need to significantly increase the volume of food consumed.

Dieting in pregnancy is not recommended. Avoid foods rich in fats and sugars and replace these with fruits and vegetables. Ensure you eat breakfast and watch portion sizes.


If you are struggling to understand and apply pregnancy food recommendations to your lifestyle you can always be referred to a dietician who specialises in pregnancy to help you through this confronting and sometimes confusing time.

Keep moving

Exercise is still important in pregnancy and this should be tailored to the individual. If a woman normally runs marathons then a 5km run would probably be okay in the first half of the pregnancy but for most women this would not be recommended. I would also not recommend pursuing sports where you could lose your balance and fall on your abdomen, especially in the 3rd trimester when your centre of gravity is significantly altered.

Although you may increase your heart rate during exercise it is not recommended to sustain a high heart rate for a prolonged period of time. Around 30 minutes of moderate intensity activity is recommended. You are more likely to maintain an exercise routine in pregnancy if you incorporate it into your daily life and build activity into everyday life (eg. take the stairs instead of the lift).

Once baby arrives

The six to eight week postnatal visit should be used as an opportunity to ask about weight gain during pregnancy and subsequent weight loss and doctors should offer access to dieticians and specialised pregnancy postnatal exercise classes, often run by physiotherapists, with focus also on pelvic floor strength and stability.

Find a health practitioner near you with Healthshare or view Dr Robyn Lloyd's full profile.