Monash-led World's Study Of 1.3 Million Pregnant Women Reveals Global Obesity Crisis

Date: 07/06/17

The world’s largest and most  comprehensive international study of more than 1.3 million pregnant women, led  by researchers at the Monash University in Melbourne, Australia has found that  three out of every four pregnant women worldwide, and their healthcare teams,  are failing to achieve a healthy weight gain during pregnancy, leading to  preventable adverse health consequences for women and their babies.

The study, published in the Journal of  the American Medical Association (JAMA), highlights the disturbing high rate of  excess unhealthy weight in mothers at the start of pregnancy and shows that the  vast majority of women are not achieving healthy recommended weight gain in  pregnancy.
In addition, the researchers found  mothers are gaining too much weight during pregnancy, increasing health  risks during pregnancy and beyond, and increasing risks for their children to  be overweight or obese.

The research team, led by Professor  Helena Teede and Dr Rebecca Goldstein from the Monash University Faculty of  Medicine, Nursing and Health Sciences, reviewed more than 5300 studies and in a  large scale international collaboration, reanalysed and integrated pregnancy  data from 23 groups across Europe, Asia and the United States.

The study sought to affirm the relevance  of older US guidelines for healthy weight gain in pregnancy. These 1990  Institute of Medicine Guidelines were originally based on 1980 data of a  largely Caucasian population. Updated in 2009, these guidelines, “were still  based on women with a lower general weight than our current population of  mothers with limited ethnic diversity,” Dr Goldstein says. While these  guidelines are endorsed by the American College of Obstetricians and  Gynaecololgists “they are not universally implemented,” with considerable lost  prevention opportunities, the JAMA paper authors add.

The Monash-led international study –  which included a broad range of ethnically diverse pregnant women, explored  their weight gain during pregnancy, their health and the health of their babies  – had key findings according to Professor Teede that include that, at the time  of pregnancy:

  • 7% women were  underweight
  • 55% normal weight
  • 38% were  overweight and obese

During pregnancy striking 3 in 4 women  did not gain healthy recommended weight with increased risks for mothers and  babies with:

  • 23% gaining less  than healthy weight gain
  • Strikingly almost  half gaining more than healthy weight gain, with higher rates in western  countries

Women who gained more than recommended were at higher risk of having large babies and requiring a  caesarian birth.
Women who gained less than the recommended weight during pregnancy were at increased risk of having  smaller babies and preterm birth.
Importantly the study found that entering  pregnancy underweight and failing to put on recommended weight during pregnancy  led to:

  • 8% risk of having  an underweight baby
  • 8% increase in preterm  birth

Professor Teede said that current study  “represents the largest contemporary international snapshot of women’s weight  coming into pregnancy and their weight gain during pregnancy, how this is  impacting of their and their baby’s health and the healthcare system.”

Importantly the study takes into account  “our more contemporary population of mothers who are increasingly entering  pregnancy at an unhealthy weight and it covers the diversity of race across  Europe, US and Asia,” Professor Teede said.

Professor Teede said that the new  evidence published in JAMA emphasises the need for urgent strategies to  monitor, support women and optimise healthy weight in mothers both before and  during pregnancy, endorsing guidelines recommending that women gain between  12.5-18kg for underweight women, 11.5-16kg for healthy weight women, 7-11kg for  overweight women and 5-9kg for obese women during pregnancy.

In 2015 Professor Teede led a team which  produced the National Health and Medical Research Council (NHMRC) Case for  Evidence-Based Action in obesity prevention, calling for vital lifestyle  intervention in preconception and pregnancy.   “The case for action aligns with WHO recommendations to prioritise  prevention of excess weight gain in reproductive aged women before and during  pregnancy,” she said. “This latest study means   - more than ever - that weight needs to be monitored in pregnancy and  women provided with support to improve lifestyle. Health professionals need to  be encouraged and trained in having "healthy conversations"  introducing relatively simple effective lifestyle interventions to support  women before, during and after pregnancy. For health services and policy makers  recognition that effective simple health lifestyle interventions are available  and now need to be incorporated into routine care to optimise reach and  availability for all women". We know what to do and now need to implement  the available evidence into action.

MCHRI and Monash University are working  towards these goals.

For further information about this  research, please email Dr Rebecca Goldstein.