Maternal Mortality in Canada

The Maternal Mortality in Canada fact sheet provides surveillance results on recent trends in maternal mortality in Canada for the years 1996-2010. Included are the rates of maternal mortality by year, associated diagnosis, age group and province and territory. The maternal mortality rate is defined as the number of maternal deaths (occurring during pregnancy, childbirth, or within 42 days after delivery or termination of pregnancy) divided by the number of deliveries, expressed per 100,000 deliveries.

Table of Contents

• List of Figures
• List of Data Tables
• Summary of Results
• Data Tables
• Definition
• Data Source
• Limitations
• References

List of Figures

• Figure 1: Maternal mortality rates in Canada, (excluding Quebec), 1996/1997 - 2009/2010
• Figure 2: Diagnoses associated with maternal deaths in Canada, (excluding Quebec), 2002/03 - 2009/10

List of Data Tables

• Table 1: Table 1: Maternal mortality rates in Canada, (excluding Quebec), 1996/1997 - 2009/2010
• Table 2: Diagnoses associated with maternal deaths in Canada, (excluding Quebec), 2002/2003 - 2009/2010
• Table 3: Maternal mortality rates by province and territory of occurrence in Canada, (excluding Quebec), 1996/1997 - 2009/2010
• Table 4: Maternal mortality rates by age in Canada, (excluding Quebec), 1996/1997 - 2009/2010

Summary of Results (excludes Quebec)

• In 2008/09-2009/10, there were 7.8 (95% CI: 5.7-10.5) maternal deaths per 100,000 deliveries in Canada (Figure 1, Table 1).
• Over the 1996/97-2009/10 period, maternal mortality rates fluctuated from a low of 6.8 (95% CI: 4.8-9.4) maternal deaths per 100,000 deliveries in 2004/05-2005/06 to a high of 11.9 (95% CI: 9.1-15.4) maternal deaths per 100,000 deliveries in 2000/01-2001/02 (Figure 1, Table 1).
• The most common diagnoses associated with these deaths were diseases of the circulatory system; other indirect causes (e.g., diseases of the digestive system and mental disorders and diseases of the nervous system complicating pregnancy, childbirth and the puerperium); hypertension complicating pregnancy, childbirth and the puerperium; postpartum hemorrhage; obstetric embolism; ectopic pregnancy and abortive outcome; major puerperal infection; and antepartum hemorrhage, abruptio placentae and placenta previa (Figure 2, Table 2).
• For 1996/97-2009/10, the late maternal mortality rate was 5.3 (95% CI: 4.6-6.1) maternal deaths per 100,000 deliveries. Neoplasms and injury, poisoning or external causes (e.g., unintentional poisoning) were the most commonly associated diagnoses in these deaths.
• Maternal mortality varied by province and territory ranging from 0 to 20.3 (95% CI: 5.5-51.9) deaths per 100,000 deliveries (Table 3).
• Maternal mortality rates increased with age. Women over 40 years old had 3.7 (95% CI: 2.2-6.1) times the rate experienced by women aged 20-24 years (Table 4).

 

Data Tables

Table 1: Maternal mortality rates in Canada, (excluding Quebec), 1996/1997 - 2009/2010

Year	N	Rate per 100,000 deliveries	95% CI
Source: Canadian Institute for Health Information, Discharge Abstract Database Note: Manitoba data, which were incomplete for earlier years, were included from 2004/05.
1996/97-1997/98	51	9.9	7.4-13.0
1998/99-1999/2000	38	7.6	5.4-10.4
2000/01-2001/02	58	11.9	9.1-15.4
2002/03-2003/04	50	10.2	7.6-13.5
2004/05-2005/06	36	6.8	4.8-9.4
2006/07-2007/08	52	9.3	6.9-12.2
2008/09-2009/10	45	7.8	5.7-10.5
Total	330	9.0	8.1-10.0

Table 2: Diagnoses associated with maternal deaths in Canada, (excluding Quebec), 2002/2003 - 2009/2010

Diagnosis	N	Maternal mortality rate per 100,000 deliveries	95% CI
Source: Canadian Institute for Health Information, Discharge Abstract Database Notes: Diagnoses do not represent underlying cause of death. Cases could have more than one associated diagnosis hence sum of individual diagnoses exceeds the overall maternal mortality rate. Manitoba data, which were incomplete for earlier years, were included from 2004/05.
Ectopic and molar pregnancy/abortive outcome	19	0.9	0.5-1.4
Antepartum hemorrhage, abruptio placentae, and placenta previa	15	0.7	0.4-1.1
Hypertension complicating pregnancy, childbirth and the puerperium	34	1.6	1.1-2.2
Postpartum hemorrhage	34	1.6	1.1-2.2
Major puerperal infection	18	0.8	0.5-1.4
Obstetric embolism	30	1.4	0.9-2.0
Diseases of circulatory system	67	3.1	2.4-3.9
Other indirect causes	44	2.0	1.5-2.8

Table 3: Maternal mortality rates by province and territory of occurrence in Canada, (excluding Quebec), 1996/1997 - 2009/2010

Province/Territory	N	Rate per 100,000 deliveries	95% CI
* suppressed due to cell size less than 5 Source: Canadian Institute for Health Information, Discharge Abstract Database Note: Manitoba data, which were incomplete for earlier years, were included from 2004/05.
Newfoundland and Labrador	11	16.4	8.2-29.3
Prince Edward Island	*	20.3	5.5-51.9
Nova Scotia	7	5.6	2.2-11.4
New Brunswick	6	5.8	2.1-12.6
Ontario	186	9.8	8.4-11.2
Manitoba	5	5.5	1.8-12.9
Saskatchewan	11	6.3	3.1-11.2
Alberta	46	8.0	5.9-10.7
British Columbia	53	9.2	6.8-12.0
Yukon	*	20.1	0.5-112.1
Northwest Territories	0
Nunavut	0
Canada	330	9.0	8.1-10.1

Table 4: Maternal mortality rates by age in Canada, (excluding Quebec), 1996/1997 - 2009/2010

Age	N	Rate per 100,000 deliveries	95% CI
Source: Canadian Institute for Health Information, Discharge Abstract Database Note: Manitoba data, which were incomplete for earlier years, were included from 2004/05.
15-19	17	8.9	5.2-14.3
20-24	41	6.6	4.7-8.9
25-29	94	8.6	7.0-10.6
30-34	84	7.5	6.0-9.2
35-39	70	13.2	10.3-16.7
≥40	24	24.4	15.6-36.2
Total	330	9.0	8.1-10.0

Definition

The maternal mortality rate is defined as the number of maternal deaths (occurring during pregnancy, childbirth, or within 42 days after delivery or termination of pregnancy) divided by the number of deliveries, and expressed per 100,000 deliveries. The definition of maternal death under the International Classification of Diseases, Ninth and Tenth Revision (ICD-9, ICD-10) is: "The death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and the site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management but not from accidental or incidental causes." Maternal deaths are considered to be direct or indirect. Direct obstetric deaths are deaths resulting from obstetric complications of the pregnant state (pregnancy, labour and puerperium), from interventions, omissions or incorrect treatment, or from a chain of events resulting from any of the above. Indirect obstetric deaths are deaths resulting from previous existing disease or disease that developed during pregnancy and which was not due to direct obstetric causes, but which was aggravated by the physiologic effects of pregnancy. Late maternal death is defined as the death of a woman from direct or indirect obstetric causes more than 42 days but less than one year after termination of pregnancy.

Data Source

Data from the Discharge Abstract Database (DAD) of the Canadian Institute of Health Information (CIHI) were used to identify in-hospital deaths among women of reproductive age (15-54 years) in Canada (excluding Quebec). Manitoba data, which were incomplete for earlier years, were included from 2004/05.

The rates are calculated based on fiscal years (i.e., April 1 to March 31).

Causes of death were coded according to ICD-9, Chapter XI: Complications of Pregnancy, Childbirth and the Puerperium (630-676) and ICD-10, Chapter XV: Pregnancy, Childbirth and the Puerperium (O00-O99).

This report uses CIHI data rather than the more traditional Vital Statistics data because recent papers by the Canadian Perinatal Surveillance System have shown that hospitalization data are more comprehensive and timely.^1,2

Limitations

The DAD does not include data from Quebec. Data from Manitoba were excluded from some analyses because they were incomplete for the early years of the study. The small number of deaths that occurred outside the hospital were not identified. The DAD data include multiple diagnostic codes for each maternal death, but do not assign an underlying cause of death. Therefore, maternal mortality rates by cause of death cannot be presented from these data.

References

1. Lisonkova S, Bartholomew S, Rouleau J, Liu S, Liston RM, Joseph KS; for the Maternal Health Study Group of the Canadian Perinatal Surveillance System. Temporal trends in maternal mortality in Canada I: Estimates based on Vital Statistics data. J Obstet Gynaecol Can 2011;33(10):1011-1019.
2. Lisonkova S, Liu S, Bartholomew S, Liston RM, Joseph KS; for the Maternal Health Study Group of the Canadian Perinatal Surveillance System. Temporal trends in maternal mortality in Canada II: Estimates based on hospitalization data. J Obstet Gynaecol Can 2011;33(10):1020-1030.