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Multiple Birth Rate

When a woman is pregnant with more than one baby this is called a multiple pregnancy.  The multiple birth rate is the percentage of all births that are multiple births in a population per year.  These data come from the Vital Statistics database.

Multiple pregnancy babies are more likely to be born prematurely and are therefore smaller and at greater risk for adverse health outcomes such as respiratory failure, gastrointestinal and immunological deficiencies and long-term challenges such as cerebral palsy (1).

Figure 1 below shows the multiple birth rate for Simcoe Muskoka and Ontario from 1986 to 2006. There has been a small increase in the percentage of multiple births from approximately 2% to approximately 3% of all births per year in both Simcoe Muskoka and Ontario.  This may be due to the increase in fertility treatments during those years, which can result in more multiple births. The Simcoe Muskoka multiple birth rate has more peaks and valleys than the Ontario multiple birth rate in the graph below because it is based on smaller numbers and thus has more variability. 

Figure 1: