Obese women more likely to have a C-section

New research shows obese pregnant women are more likely to have a caesarean, take longer to treat and have a higher risk of complications.

The MUM SIZE study of 1500 women by Melbourne University looked at the time the women spent under anaesthetic care, and how a woman’s weight impacted on operating room times for caesarean delivery.

The study found a caesarean section took 25 per cent longer for a very obese woman (BMI of 45 and over), and 10 per cent longer for an obese woman (BMI 35-45).

Lead investigator Professor David Story, Chair of Anaesthesia at the University of Melbourne says one of the factors is that it’s more difficult to administer a drip and a spinal tap (which numbs the lower body) in obese patients.

"The difficulty is getting the needle in the right place because it’s a lot harder to find the tips of the backbone,” says Professor Story.

The aim of the study is to understand the best ways for anaesthetists to treat and care for women giving birth by caesarean.

“I think there has been a marked increase (in the number of obese woman giving birth), but the feeling is it really just reflects the over all figures in society,” says Professor Story.

Bupa’s accredited practising dietitian Christine Wong says while it’s important obese women try to lose weight before falling pregnant, it’s not recommended women lose weight when they’re expecting.

“It’s about making sure they are eating very nutrient dense foods,” says Wong.

pregnant woman at doctor

The institute of medicine guidelines (2009) recommends that women at a healthy weight (BMI 18.5-24.9) shouldn’t put on more than 11-16 kg, and overweight or obese women (BMI >30) shouldn’t put on more than 5-9kg. 

Wong says all women should consult their doctor about maintaining a healthy weight while pregnant.

Professor Story says it’s hoped more information on the risks of obesity in pregnancy will help women plan ahead.

“What we want is for people to live longer, healthier, happier lives,” says Professor Story.

“Once they’ve had their baby, then it’s a time to consider an approach to weight loss,” he says.

According to the Australian Institute of Health and Welfare, almost two in three Australian adults are overweight and obese. The number of those who are morbidly obese is rising.

The Australian and New Zealand College of Anaesthetists (ANZCA) says over the past 20 years obesity has become one of the biggest issues in the management of patients.

ANZCA President Dr Genevieve Goulding says obese people often have other health problems like type 2 diabetes, high blood pressure, heart disease and sleep apnoea which can lead to complications in surgery.

She says in some cases that can place patients at higher risk, or it could be too risky to perform surgery at all.

“It is important for every patient expecting elective surgery to discuss the risk associated with excess weight with their medical team, including their anaesthetist,” says Dr Goulding.

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