Map(s) of the Week: Childbirth, week 4

TARA WALTON/TORONTO STAR

This week winds up our series on childbirth in the GTA with a look at homebirth and midwifery.

The information comes from data I bought from the Office of the Registrar-General, which was taken from the Statement of Live Birth form (.pdf) which is filled out when a child is born in Ontario. 

All the maps are based on the first three characters of the postal code of the mother, and show data from 2007, the most recent year available. Postal codes with fewer than 30 births have been dropped from the map this week.

Birth: Percentage of homebirths, 2007

Birth: Percentage of babies delivered by midwives, 2007

No distinction is made on the form between planned and unplanned homebirths.

Perhaps not surprisingly, the maps look roughly similar, with strong clusters in the old east and west ends of the central city, the west-end cluster being bigger. The midwifery map has a cluster in northern York Region roughly along the 400, and another in Burlington.

Here are the top 10 neighbourhoods for midwife-delivered babies:

M6R	Toronto: High Park/Roncesvalles	13.88%
M6G	Toronto: Little Italy: Seaton Village	12.87%
L9N	East Gwillimbury: Holland Landing	11.39%
M6S	Toronto: Bloor West Village/Swansea	10.17%
M4M	Toronto: South Riverdale	10.13%
M6P	Toronto: Bloor West Village/High Park	9.65%
M6H	Toronto: Trinity/Niagara	9.16%
M4L	Toronto: Leslieville/western Beaches	8.89%
M4J	Toronto: Trinity/Niagara	8.84%
M5C	Toronto: Jarvis/Queen/Yonge/King	8.82%

and the top 10 for homebirths:

M6R	Toronto: High Park/Roncesvalles	6.12%
L1W	Pickering: lakeshore area	6.00%
M5C	Toronto: Jarvis/Queen/Yonge/King	5.88%
M5B	Toronto: Ryerson area	5.19%
M6H	Toronto: Ossington/St. Clair/tracks/Dufferin	5.09%
M4M	Toronto: South Riverdale	5.06%
M4L	Toronto: North Toronto (N of Eglinton/Mount Pleasant)	4.65%
M6G	Toronto: Little Italy: Seaton Village	4.62%
M4P	Toronto: North Toronto (N of Eglinton/Mount Pleasant)	4.49%
M6P	Toronto: Bloor West Village/High Park	4.31%

For simplicity’s sake, the data order I placed with the Registrar-General covered the L- and M-series postal codes, which roughly works out to all of south-central Ontario, including Hamilton, Niagara and the area stretching north to Georgian Bay. The maps haven’t shown areas outside the GTA*, but I’ve been keeping an eye on that data.

Last week (Map: No other parent listed, 2007), I probably should have pointed out that two Hamilton neighbourhoods (L8L, more or less the North End, and adjoining L8M, a box bounded by Main St. E./the escarpment/Upper Wentworth/Ottawa Street) also have very high rates of single motherhood, and would have made a top 10 list if we were depicting all of south-central Ontario.

This week, the data shows that the Hamilton area has a much higher rate of midwife deliveries than anywhere else in south-central Ontario. Here is the top 10 list for midwife deliveries, if we look at this whole area (.pdf):

L9G	Suburban (non-rural) Ancaster	18.52%
L9H	Dundas	15.81%
L8S	Hamilton: McMaster/Westdale area	15.70%
L8P	Hamilton: 403/escarpment/King/James	15.68%
L8R	Hamilton: Roughly 403/King/James/harbour	14.06%
M6R	Toronto: High Park/Roncesvalles	13.88%
L2S	East Gwillimbury: Holland Landing	12.90%
M6G	Toronto: Little Italy: Seaton Village	12.87%
L9N	East Gwillimbury: Holland Landing	11.39%
L0S	Niagara Region: Eastern rural areas	11.37%

**

Here is the equivalent home birth table:

M6R	Toronto: High Park/Roncesvalles	6.12%
L1W	Pickering: lakeshore area	6.00%
M5B	Toronto: Ryerson area	5.19%
M6H	Toronto: Ossington/St. Clair/tracks/Dufferin	5.09%
M4M	Toronto: South Riverdale	5.06%
L0A	Northumberland County: western area	4.76%
L3C	Toronto: Little Italy: Seaton Village	4.71%
M4L	Toronto: Leslieville/western Beaches	4.65%
M6G	Toronto: Little Italy: Seaton Village	4.62%
M4P	Toronto: North Toronto (N of Eglinton/Mount Pleasant)	4.49%

**

I'm conscious with all these map projects that there are readers who know far more about any given subject than I do - I'm just a guy with some data and some tools. Here are some questions for readers:

1) Looking at this data, there seems to be a greater proportion of hospital deliveries by midwives outside the central city (in Hamilton and York Region, for example), and a greater proportion of home births downtown. Is there a reason? Both of our children were born at home in Riverdale, and I found it reassuring that if anything went wrong there were major hospitals within easy reach. Does it have to do with closeness to hospitals, or cultural differences between midwife practices?

2) In Toronto, the map of midwife deliveries roughly tracks the location of midwife practices. (map: zoom in to see Toronto in detail). Is this supply, demand, or something of both?

---

* There are several reasons. One is that the boundaries on the maps have to be built by hand in a labour-intensive process, and adding postal areas outside the GTA would have involved creating another 67 polygons, or two-dimensional shapes. Another is that the maps are slow to load as it is (especially in IE) and I’m reluctant to slow them down further. Another is that several areas (Dufferin County and Niagara) have rural postal codes which completely enclose urban postal codes, and the XML system we’re using doesn’t allow for doughnut polygons (I’m aware that conventional geoKML does and and also GoogleMaps v3, as of this week).

** Two low-population postal codes excluded

Comments

[Marcel Fortin]

Just curious about the legend. You have 0-2% and 1-2%. Can you explain or is it an error?

[pcain]

Error. Corrected now. Tx for pointing it out -