Pregnancy Weight Gain: How Much Weight Is Healthy To Gain During Pregnancy?

A recent international study of 1.3 million pregnant women, led by researchers at Monash University revealed that three in four women did not gain the recommended weight during pregnancy, with more than half gaining more weight than necessary.

Lead author Professor Helena Teede said the study highlights the increasing trend of women failing to maintain a healthy weight during pregnancy, leading to preventable negative health outcomes for both the expecting mother and her baby.

Three in four women are failing to maintain a healthy weight during pregnancy.

“This latest study means — more than ever — that weight needs to be monitored in pregnancy and women provided with support to improve lifestyle,” Prof Teede says.

Given the potential harm — both short and long-term — of unhealthy weight gain for both the mother and child, experts are calling for discussions about healthy weight gain and how to achieve it through diet and physical activity as part of a regular pregnancy health check-up.

“Very few women know how much weight they should be gaining throughout their pregnancy,” Dr Karen Campbell, from Deakin University’s Institute for Physical Activity and Nutrition (IPAN), says. “The amount of weight that is healthy to gain depends on your starting weight.”

RendezView. Pregnant woman is showing her Ultrasound. (Pic: iStock)

She says women with a higher body mass index (BMI) at the start of pregnancy will need to gain less weight than women with a lower starting BMI because they already have adequate adipose reserves (fatty tissue) to support pregnancy and lactation.

“At the moment we know in Australia that around half of all women enter pregnancy overweight or obese, and women who are overweight or obese before pregnancy tend to get fatter and have children who are at increased risk of obesity and other chronic diseases later in life,” she says. “They are also more likely to develop gestational diabetes or pre-eclampsia.”

Women who gain more weight than recommended have a higher risk of having large babies and requiring a caesarean birth, and may have greater difficulty losing weight after childbirth.

While there are many challenges for women during pregnancy, Dr Campbell says weight is “by far” one of the biggest. It is also one of the least spoken about.

Experts are calling for regular weigh-ins to become part of standard pregnancy health check ups.

“Our own research tells us that while doctors and midwives are very aware that weight is important they are reluctant to talk about it,” she says. “There are already so many things women need to know during pregnancy that health practitioners often avoid the topic of weight for fear of upsetting already stressed out mothers.

“While it’s quite easy to tell someone what not to do — stay away from soft cheeses, avoid alcohol, limit caffeine intake, all important in pregnancy — supporting pregnant women to eat healthfully across pregnancy requires substantial engagement and time; time which health practitioners usually don’t have.”

And it’s not enough to just weigh someone at the start and at the end, once it is already too late. The key is being able to provide feedback, assistance and support the whole way through.

“We’re fascinated by the potential of low-cost, broad-reaching programs to support women to achieve healthy diet, physical activity and weight gain in pregnancy. Smart phones and text-based approaches may just help us here.

Text-based intervention has been shown to help women stick to their diet or physical activity goals.

“We conducted a study recently where overweight or obese women got several text messages a week to help them achieve their diet or physical activity goals,” Dr Campbell says. “The aim was to reduce the amount of weight they gained during pregnancy and there was a 2kg difference between women who had the intervention and those who didn’t.”

This early research suggests that with very low cost and easy to roll out interventions, practitioners are well placed to make a real difference to the way women experience pregnancy.

“Research shows when women know how much weight is appropriate to gain they are more likely to keep within those boundaries,” she says. “During pregnancy they are primed to do the best for their babies, so the aim of any pregnancy weight management program is to tap into that desire.”

*Weight gain in pregnancy can be affected by factors other than diet and exercise. If you are concerned, see your doctor.