Postcode key in rate of caesareans, with link to obesity

The rate of caesareans being performed in Australia varies by up to three times depending on where women give birth.

Report co-author Rebecca Goldstein, at home in Melbourne, is pregnant with her third child. Picture: David Geraghty

The rate of caesareans being performed in Australia varies by up to three times depending on where women give birth, with the nation’s rising obesity rate likely to be a contributing factor.

A report today from the Australian Commission on Safety and Quality in Health Care charts the variation in rates of a series of interventions, raising the need for further investigation into ­whether some communities are potentially being over-serviced and others under-serviced.

The report shows the caesarean rate is increasing overall but also varies widely by statistical area for women aged 20-34. The highest rates are in Bribie ­Island and Beachmere in Queensland (438 per 1000 women), outback north and east South Australia (400), Glenelg-Southern Grampians in Victoria (393) and Inverell and Tenterfield in NSW (389).

By contrast, the lowest rates are in Baw Baw in Victoria (147), Fairfield in NSW (168), and Port Douglas and the Daintree in Queensland (170), and Stonnington East in Victoria (173).

While caesarean section can be medically necessary and in some cases lifesaving, it comes with its own risks for mother and baby. Identifying variation may help experts determine acceptable rates and other potential ­interventions.

“For women at most socio-economic advantage, private health insurance coverage and maternal preference are likely to be important contributors,” the commission concluded, with the caesarean rate also shown to be 1.4 times higher among privately funded patients.

“For women at least socio-economic advantage, higher rates of medical and obstetric complications are likely to drive rates of caesarean section.”

The commission suggested obesity might be a factor, as a major study of 1.3 million pregnant women worldwide found 38 per cent were overweight and obese, with higher risk of having large babies and requiring a caesarean birth.

The study, led by researchers at Melbourne’s Monash Univer­sity and published today in the Journal of the American Medical Association, found almost half of the women put on more than the recommended weight gain.

Lead author Helena Teede said the study found mothers were “increasingly entering pregnancy at an unhealthy weight”, putting themselves and their unborn children at risk. “This latest study means ... weight needs to be monitored in pregnancy and women provided with support to improve lifestyle,” she said.

Co-author Rebecca Goldstein, an endocrinologist and PhD candidate, is pregnant with her third child. With two healthy children, Dr Goldstein has managed to avoid the need for a caesarean and hopes her next delivery is also without complication.

She said US guidelines for healthy weight gain in pregnancy, updated in 2009 and not universally implemented, were “still based on women with a lower general weight than our current population of mothers with limited ethnic diversity”.

The guidelines recommend women gain 12.5kg-18kg if underweight, 11.5kg-16kg if of healthy weight, 7kg-11kg if overweight and 5kg-9kg if obese.