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6B Multiple Birth Rate

Description | Specific Indicators | Ontario Public Health Standards | Corresponding Health Indicator(s) from Statistics Canada and CIHI | Corresponding Indicator(s) from Other SourcesData Sources |  Alternative Data Sources |  Analysis Check List | Method of Calculation |  Basic Categories | Indicator Comments | Definitions | Cross-References to Other Indicators | Cited References  | Changes Made | Acknowledgements 


  • The ratio of births following a multiple gestation pregnancy per total births
Specific Indicators
  • Multiple Birth Rate
  • Multiple Live Birth Rate
Ontario Public Health Standards (OPHS)
The Ontario Public Health Standards (OPHS) establish requirements for the fundamental public health programs and services carried out by boards of health, which include assessment and surveillance, health promotion and policy development, disease and injury prevention, and health protection. The OPHS consist of one Foundational Standard and 13 Program Standards that articulate broad societal goals that result from the activities undertaken by boards of health and many others, including community partners, non-governmental organizations, and governmental bodies. These results have been expressed in terms of two levels of outcomes: societal outcomes and board of health outcomes. Societal outcomes entail changes in health status, organizations, systems, norms, policies, environments, and practices and result from the work of many sectors of society, including boards of health, for the improvement of the overall health of the population. Board of health outcomes are the results of endeavours by boards of health and often focus on changes in awareness, knowledge, attitudes, skills, practices, environments, and policies. Boards of health are accountable for these outcomes. The standards also outline the requirements that boards of health must implement to achieve the stated results.

Outcomes Related to this Indicator 
  • Board of Health Outcome (Reproductive Health): The board of health is aware of and uses epidemiology to influence the development of healthy public policy and its programs and services for the promotion of reproductive health.
  • Board of Health Outcome (Foundational Standard): The public, community partners, and health care providers are aware of relevant and current population health information Assessment and/or Surveillance Requirements Related to this Indicator. 
Assessment and Surveillance Requirements Related to this Indicator (Reproductive Health) 
  • The board of health shall conduct epidemiological analysis of surveillance data... in the area of reproductive health outcomes. 

Corresponding Health Indicator(s) from Statistics Canada and CIHI
  • None
Corresponding Indicators from Other Sources
  • None
Data Sources (see Resources: Data Sources) 
Note that 3 data sources are listed for use: 1) Vital Statistics, 2) Hospitalization, 3) BORN. The choice of data source will depend upon data quality within a health unit as well as data access and the specific analysis questions. For information related to the data sources, refer to the Data Source resources and the Reproductive Health Core Indicators Documentation Report. 

Alternative 1
Numerator & Denominator: Vital Statistics Live Birth Data
Original source: Vital Statistics, Office of Registrar General (ORG), ServiceOntario
Distributed by: Ontario Ministry of Health and Long-Term Care (MOHLTC): IntelliHEALTH ONTARIO (IntelliHEALTH)
Suggested citation (see Data Citation Notes): Ontario Vital Statistics Live Birth Data [years], Ontario Ministry of Health and Long-Term Care, IntelliHEALTH ONTARIO, Date Extracted: [date].

Alternative 2

Numerator & Denominator: Hospitalization Data
Original source: Discharge Abstract Database (DAD), Canadian Institute for Health Information (CIHI)
Distributed by: Ontario Ministry of Health and Long-Term Care (MOHLTC): IntelliHEALTH ONTARIO (IntelliHEALTH)
Suggested citation (see Data Citation Notes): Inpatient Discharges [years], Ontario Ministry of Health and Long-Term Care, IntelliHEALTH ONTARIO, Date Extracted: [date].

Alternative 3
Numerator & Denominator: BORN Information System
Original source: Better Outcomes Registry Network (BORN) Ontario
Distributed by: Better Outcomes Registry Network (BORN) Ontario
Suggested citation (see Data Citation Notes): BORN Information System [years], Date Extracted: [date].

Alternative Data Sources 
  • None
Analysis Check List
  • Include stillbirths if calculating 'Multiple Birth Rate' and exclude if calculating 'Multiple Live Birth Rate'.
  • The IntelliHEALTH licensing agreement does not require suppression of small cells, but caution should be used when reporting at a level that could identify individuals, (e.g. reporting at the postal code level by age and sex). Please note that privacy policies may vary by organization. Prior to releasing data, ensure adherence to the privacy policy of your organization.
  • Aggregation (e.g. combining years, age groups, categories) should also be considered when small numbers result in unstable rates.
  • Exclude births to mothers that reside out-of-province. Births to Ontario mothers that occur out-of-province are not included in the data.
  • Include all births, not just those for mothers aged 15-49 years.
  • Include live births with birth weights <500g. For more information, refer to the Reproductive Health Core Indicators Documentation Report.
  • HELPS Data: Historically, PHUs obtained data for live births, stillbirths, therapeutic abortions, congenital anomalies, and deaths from the Ministry of Health through HELPS (the HEalthPlanning System). Although these data are no longer commonly used, some PHUs may still be accessing these data files. Information about the data can be found in the HELPS Data Source resource.
Vital Statistics Live Births 
  • In IntelliHEALTH under Standard Reports, folder "01 Vital Stats", open "Birth Summary V2". This report summarizes information on births by age group and mother's residence (Ontario, PHU and LHIN). IntelliHEALTH also provides population data (total population, female population aged 15-49 years) for the calculation of rates. Refer to the Notes tab for information. Open tab "1.2 Births x PHU x Type x Age" to obtain public health unit data and tab "1.1 ON Births x Type x Age" to obtain Ontario data. The report can be modified, renamed and saved under your own folder or can be exported into Excel.
  • The predefined report provides birth and population data for the calendar years from 1986 to the most recent available. Table options can be edited to change the number of years of data presented. For years that are not displayed modify the calendar year filter to include the required years.
  • Type of birth includes the categories single birth, twins, triplets, quadruplets, quintuplets with each broken down by live births and stillbirths, and summed for total births.
  • The data contained in the Birth Summary v2 report includes births to Ontario mothers in Ontario only.
  • The notes section of the report provides important data caveats and information and should be consulted.
  • Refer to the Vital Statistics Live Birth Data Source and Vital Statistics Stillbirth Data Source for more information about the data.
  • Under the Inpatient Discharge Main Table data source from the ‘05 Inpatient Discharges' folder, use the "Hospital births x births, delivery type" predefined report. This report can be modified, renamed and saved under your own folder.
  • The report provides hospital birth counts (Admit Entry Type = N for Newborn or S for Stillbirth) for Ontario and by PHU, including only Ontario residents (Patient Province equal to ON).
  • The calendar year for date of admission is used (Admit CYear) rather than date of discharge since the date of admission will be the same as the birthdate for newborns.
  • Even though counts are grouped by calendar year of admission, it is the actual number of discharges that are counted. 
  • The field "ICD10-CA Code All Dx" provides detailed information about singleton and multiple births. This information is available in the predefined report or can be selected with filter "ICD10-CA Code All Dx matches pattern Z38*".
  • Multiple birth information is available from CY2003 onwards.
BORN Information System
  • Public Health Units access BORN data through public health reports and data cubes.
  • Refer to the BORN Information System resource for details about the data.
Method of Calculation
Multiple Birth Rate:

total number of multiple births (live births & stillbirths)

x 100

total number of births (live births & stillbirths)

Multiple Live Birth Rate: 

total number of multiple live births

x 100

total number of live births

Basic Categories  
  • Multiple births: all twins, triplets, quadruplets, quintuplets, and higher-order births
  • Multiple live births
  • Mother's age; gestational age
  • Geographic areas of patient residence:
    • Vital Statistics, Hospitalization data: Ontario, public health unit, municipality, and smaller areas of geography based on aggregated postal code.
    • BORN data: Ontario, public health unit
Indicator Comments
  • Mothers with multiple gestation pregnancies are more likely to have anemia, pre-eclampsia, preterm labour and caesarean delivery, while multiple birth infants are more likely to experience low birth weight, poor fetal growth, preterm birth, and perinatal death (1).
  • In the long term, children born from a multiple birth may be at increased risk for cerebral palsy and other neurodevelopmental disabilities (2).
  • The multiple birth rate has increased in Canada from 2.2 per cent of total births in 1995 to 3.0 per cent in 2004 (3).
  • The upward trends in multiple birth rates are likely the result of increased use of assisted reproductive technology (ART) in Canada to enhance fertility, as well as an increasingly older average maternal age at conception (4-6).  Older women are more likely to have natural multiple gestation pregnancies, and are also at increased risk for infertility which increases the usage of assisted reproductive technology (7).
  • Mother's age is reported at time of delivery.
  • Some reports use rate of live births while others use both live births and stillbirths.
  • Live birth - the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of the pregnancy, which, after such separation, breathes or shows any other evidence of life such as heartbeat, umbilical cord pulsation, or definite movement of voluntary muscles, whether the umbilical cord has been cut or the placenta is attached. A live birth is not necessarily a viable birth.
  • Preterm birth - a live birth that occurs at less than 37 completed weeks (i.e., <259 days) of gestation.
  • Gestational age - calculated as the interval between the date of delivery of the fetus or newborn and the first day of the mother's last normal menstrual period. Full-term pregnancies average about 40 weeks (38 to 41 weeks).
  • Stillbirth -death prior to the complete expulsion or extraction from its mother of a product of conception. The death is indicated by the fact that after such separation the fetus does not breathe or show any other evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles. Only fetal deaths where the product of conception has a birth weight of 500 grams or more or the duration of pregnancy is 20 weeks or longer are registered in Canada.
  • Multiple birth - occurs when a pregnancy results in the development of two or more fetuses.
  • Pregnancy - the gestation process, from conception through to the expulsion of the product of conception from the body whether through miscarriage, therapeutic abortion, caesarean section, or vaginal delivery.
Cross-References to Other Indicators
Cited References
  1. Lee YM, Cleary-Goldman J, D'Alton ME. The impact of multiple gestations on late preterm (near-term) births. Clin Perinatol. 2006; 33(4):777,92; abstract viii.
  2. Rand L, Eddleman KA, Stone J. Long-term outcomes in multiple gestations. Clin Perinatol. 2005;32(2):495,513, viii.
  3. Public Health Agency of Canada. Canadian perinatal health report, 2008 Edition. Available from: Accessed July 15, 2011.
  4. Blondel B, Kogan MD, Alexander GR, Dattani N, Kramer MS, Macfarlane A, et al. The impact of the increasing number of multiple births on the rates of preterm birth and low birthweight: an international study. Am J Public Health. 2002; 92(8):1323-30.
  5. Brinsden PR. Controlling the high order multiple birth rate: the European perspective. Reprod Biomed Online. 2003;6(3):339-44.
  6. Martin JA, Park MM. Trends in twin and triplet births: 1980-97. Natl Vital Stat Rep. 1999;47(24):1-16.
  7. Alexander GR, Slay Wingate M, Salihu H, Kirby RS. Fetal and neonatal mortality risks of multiple births. Obstet Gynecol Clin North Am. 2005;32(1):1,16, vii.
Changes Made 


DateType of Review - Formal or Ad HocChanges Made ByChanges Made
March 2010FormalReproductive Health Sub-GroupReplaced Mandatory Health Programs section with updated Ontario Public Health Standards outcomes.
March 30, 2012 - January 16, 2013FormalReproductive Health Sub-Group·      Three data sources cited with analysis check-list for each.
·      All births included - no longer exclude births with birth weight less than 500g.

Lead Authors

  • Jessica Deming, Region of Waterloo Public Health
  • Mary-Anne Pietrusiak, Durham Region Health Department

Contributing Authors

  • Reproductive Health Sub-Group


  • Deborah Carr, Oxford County Health Unit
  • Sherri Deamond, Durham Region Health Department (Core Indicators Work Group Member)
  • Ahalya Mahendra, Public Health Agency of Canada (Core Indicators Work Group Member)
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