Almost one in four women in Newfoundland and Labrador deliver their babies by C-section, compared with only one in 20 in Nunavut, newly released data show.
Similarly, the percentage of women getting an epidural during delivery is three times higher in Quebec than in the Yukon, and there are 2 1/2 times as many "assisted births" (involving forceps or vacuum extraction) in Alberta than in Prince Edward Island.
These are just a few striking examples of how the medical procedures women are subjected to during childbirth vary markedly between regions.
"The bottom line is that there are a lot of obstetrical interventions in Canada," said Gisela Becker, president of the Canadian Association of Midwives.
"As for the variations, there are a whole bunch of reasons," she said.
Those reasons include everything from more women giving birth over the age of 40 through to the fragmentation of care, and from overcautious risk managers through to doctors with ingrained habits.
"It's really hard to figure out what the correct rate of intervention should be," said Dr. André Lalonde, executive vice-president of the Society of Obstetricians and Gynaecologists of Canada.. "There are a lot of factors that come into play."
What is certain, though, is that the variations that exist are too great and suggest some inadequacies in care, he said.
Dr. Lalonde noted that the SOGC, concerned by the increasing rate of cesarean sections, has launched a plan to reduce the incidence of unnecessary surgery, with mixed results.
"We have some good guidelines but there is no money for implementation," he said.
There were about 374,000 hospital births in Canada last year, according to the Canadian Institute for Health Information.
Of those, 18.5 per cent were delivered by C-section and 81.5 per cent were vaginal births. The cesarean rate rose to 23.7 per cent among women over the age of 35.
Ms. Becker, a midwife in Fort Smith, NWT, said that while there are cases where surgery is required, the "World Health Organization says that a C-section rate over 15 per cent is not acceptable."
Across Canada, the number of vacuum-assisted births was almost 10 per cent, ranging from 4 per cent in PEI to 13 per cent in Saskatchewan
Forceps are used to assist delivery in 3.3 per cent of births, but again it ranges from 2.3 per cent in PEI to 5.5 per cent in Newfoundland and Labrador.
Dr. Lalonde cautioned that the assisted-birth numbers should not be used as a sign that there is too much intervention. Specialist obstetricians tend to use forceps and vacuums far more often than general practitioners, and when those tools are used the rate of C-section is much lower, he said.
Similarly, the use of epidurals does not necessarily reflect the desire of women for pain relief as much as the availability of anesthesiologists.
In Quebec, 69 per cent of women who have a vaginal delivery receive an epidural; the rate is 21 per cent in the Yukon.
About 6 per cent of babies born in Canada are of low birth weight (referred to colloquially as "preemies"), meaning they weigh less than 2,500 grams at birth. Again there is a range, from 4.9 per cent in PEI to 6.7 per cent in Alberta.