Obesity drives C-section rates higher
The larger a pregnant woman is, the greater her risk of having a caesarean section.
By Lynne Peeples
Article originally in Reuters
According to a U.S. study, the larger a pregnant woman is when she checks in on delivery day, the greater her risk of having a caesarean section.
Nearly one of every three births in the United States is now delivered by caesarean, a surgery that has been linked to complications for both mother and baby such as infection, bleeding and hysterectomy.
This rate is about 50% higher than it was in the mid-1990s, according to the U.S. Centre for Disease Control and Prevention.
"As clinicians, we are faced with so many issues when taking care of patients with higher BMI (body mass index), and one of them is a greater risk for , caesarean " researcher Dr. Michelle Kominiarek of Indiana University told Reuters Health.
She added while previous studies had already linked caesarean delivery and body mass index (BMI) -- a measure of weight that takes into account height -- none had been large or detailed enough to determine how other factors might alter that risk, such as prior births or caesarean sections.
So Kominiarek and her colleagues collected data on nearly 125,000 women from the National Institutes of Health's Consortium on Safe Labor who gave birth between 2002 and 2008.
They analyzed the circumstances surrounding each birth, as well as the delivery route.
A total of 14% of the women underwent caesareans, report the researchers in the American Journal of Obstetrics and Gynecology. They found that for every unit increase in BMI, as measured on arrival for delivery, a woman's risk of caesarean delivery rose by 4%.
The team also discovered that this risk varied depending on whether or not a woman had given birth before or had previously undergone a caesarean section.
A one-unit increase in BMI raised the risk of caesarean 5% for a woman delivering her first child, 2% for women with children and prior caesarean, and 5% for women with children but without a prior caesarean.
These effects remained after accounting for factors such as maternal age, race and cervical dilation at hospital admission.
Overall, those who had a prior caesarean had about double the risk of having another: more than 50% of labouring women with a BMI over 40, this is considered morbidly obese.
Part of the motivation for repeat caesareans is concern over a vaginal birth tearing scars left over from the previous surgery.
Other factors associated with the risk of caesarean in the current study included an age of 35 or older, black or Hispanic race, and diabetes.
Exactly how obesity contributes to caesarean risk still has not been well addressed, added Kominiarek.
"What is ultimately the safest delivery route for someone with a high BMI? Is it best to have an elective c-section, or is it just as safe to labour and then have a c-section? It will require more research to answer such questions," she said.
Are you an overweight pregnant mom-to-be? What are your thoughts on C-sections?