Number of low birth weight babies rising in Canada, reports CIHI

New analysis on birthing trends shows Caesarean-section rates, epidural use also increasing

July 25, 2007 – In 2005–2006, about one in 16 babies (6.1%) born in Canadian hospitals was underweight, weighing less than 2,500 grams (or 5.5 pounds), according to new analysis from the Canadian Institute for Health Information (CIHI). This represents a steady increase in the rate of low birth weight babies over the past five years, up from 5.7% of hospital births in 2001–2002. The low birth weight rate had been declining between 1997 and 1999.

“Some babies weighing less than five-and-a-half pounds at birth may have difficulties ahead,” said Caroline Heick, CIHI’s Director of Acute and Ambulatory Care Information Services. “For example, they may face long periods of hospitalization and have an increased risk of lifelong complications. Though the increase seems to mirror U.S. trends, it is very important to continue to monitor these rates in Canada and try to determine why, after years of progress in prenatal care, the number of babies born underweight appears to be rising again.”

CIHI’s new analysis, Giving Birth in Canada: Regional Trends From 2001–2002 to 2005–2006, provides the most up-to-date information on the birthing process in Canada, and shows notable variations in the rates of low birth weight babies across Canada. For example, among the provinces, Prince Edward Island and Manitoba reported the lowest low birth weight rate (5.0% and 5.4% respectively) in 2005–2006, while Alberta and Ontario reported the highest average provincial rates (6.9% and 6.4% respectively). Rates were even higher at the health region level within the provinces, with some regions in Newfoundland and Labrador, Nova Scotia, New Brunswick, Quebec, Ontario, and Alberta reporting low birth weight rates of over 7%.

One in four babies delivered by Caesarean section

The number of women giving birth by Caesarean section in Canada steadily increased over the past five years, climbing from 23% in 2001–2002 to 26% in 2005–2006. This is lower than the rate in the United States and Australia in 2004 (29%), though higher than the rate in England in 2005–2006 (24%). The World Health Organisation (WHO) recommends no more than 15% of all births should involve a Caesarean section.

CIHI’s analysis found that women who had a previous

Caesarean-section delivery have an 82% chance of having a repeat Caesarean section, up from 73% in 2001–2002. Women who had a Caesarean section in 2005–2006 were older than women having a vaginal delivery (30.4 years versus 28.7 years).

“Over the past five years, we’ve seen an increase in Caesarean-section rates for birth mothers in all age groups across Canada,” says Heick. “However, we do see wide variation in these rates between provinces. Some literature suggests that changes in obstetrical practice and a low tolerance for fetal risk may be contributing factors.”

At the provincial level, Caesarean-section rates ranged from lows of 21% in Saskatchewan and Manitoba to highs of 30% in Newfoundland and Labrador and British Columbia. Regionally, lows ranged from 18% in Interlake (Manitoba) and 19% in Prince Albert (Saskatchewan) to highs of 34% in the Central Health Region (Newfoundland and Labrador) and 37% in South Vancouver Island (B.C.).

Use of epidurals increasing; assisted deliveries decreasing

Epidural use also increased between 2001–2002 and 2005–2006 in most regions. More than half (54%) of all women who gave birth vaginally in 2005–2006 were given an epidural, up from 45% of all vaginal births four years earlier. The rate of epidural use varied greatly among regions, as well as among provinces and territories. In 2005–2006, provincial rates ranged from 25% in P.E.I. and 28% in B.C. to 56% in Ontario and 68% in Quebec. Rates in the territories were generally much lower, at 9.0% in Nunavut, 15% in the Northwest Territories and 32% in the Yukon Territory. Regionally, rates ranged from 9.0% in the Central Health Region (Newfoundland and Labrador) and 10% in North Vancouver Island (B.C.) to 79% in Lanaudi�re (Quebec) and 78% in Capitale nationale (Quebec).

In contrast to Caesarean-section and epidural rates, overall assisted delivery rates decreased in most regions, from 16% of births in 2000–2001 to 14% of vaginal births in 2005–2006. As an assisted delivery technique, vacuum extraction was used approximately twice as frequently as forceps, with average rates in Canada of 9.8% and 3.7% respectively in 2005–2006. At the provincial level, the lowest overall assisted delivery rates were observed in P.E.I. (6.5%) and Manitoba (8.7%), while the highest were in Newfoundland and Labrador and Alberta (17%). Regionally, lows ranged from 4.5% in Region 6 (Bathurst area) of New Brunswick and 5.4% in the Central Health Region (Manitoba), to highs of 23% in the East Central and Calgary Health Regions in Alberta.

About CIHI

The Canadian Institute for Health Information (CIHI) collects and analyzes information on health and health care in Canada and makes it publicly available. Canada’s federal, provincial and territorial governments created CIHI as a not-for-profit, independent organization dedicated to forging a common approach to Canadian health information. CIHI’s goal: to provide timely, accurate and comparable information. CIHI’s data and reports inform health policies, support the effective delivery of health services and raise awareness among Canadians of the factors that contribute to good health.