Low birth weight

Low birth weight

What is it?

Low birth weight (LBW) refers to the percent (rate) of babies born in Toronto with a birth weight of less than 2,500 grams (5.5 pounds), regardless of gestational age.

Why is it important?

Low Birth Weight has both short- and long-term consequences on health. These include higher risk of childhood illness, delays in motor development, and chronic diseases in adulthood such as diabetes and respiratory disease. A low birth weight may be the result of premature birth or restricted growth in-utero. Risk factors for LBW include maternal ages under 20 or over 35, smoking or illicit drug use during pregnancy, low socioeconomic status and multiple births (e.g. twins, triplets).

What does it mean?

In Toronto, for every 100 babies born, about 7 will be considered LBW. Figure 1 shows that percent of LBW babies varies across Ontario and that the percent of LBW babies in Toronto is higher than the rate for Ontario. Figure 2 shows that the percent of LBW babies is significantly higher in the lowest income quintile, as compared to the highest income quintile. This mean that babies born in low income neighbourhoods are more likely to have a LBW. Figure 3 displays the percent of LBW babies in the city of Toronto. While some neighbourhoods have higher rates of LBW babies, there is no statistically significant geographical trend across the city.

Figure 3: Percent of low birth weight babies by Toronto neighbourhood, 2009 to 2013