Table 1.
Variable | Number of Birthsa | Percent Preterm | ||
---|---|---|---|---|
Preterm | Term | Total | ||
Maternal age (years) | ||||
19 or less | 3515 | 38,690 | 42,200 | 8.33 |
20–29 | 33,795 | 501,050 | 534,845 | 6.32 |
30–39 | 39,760 | 587,780 | 627,540 | 6.34 |
40+ | 3800 | 39,765 | 43,565 | 8.72 |
Missing | 10 | 75 | 90 | 11.11 |
Maternal marital status | ||||
Single | 18,080 | 223,090 | 241,170 | 7.50 |
Married | 51,410 | 809,340 | 860,755 | 5.97 |
Widowed | 70 | 965 | 1035 | 6.76 |
Divorced | 1050 | 12,175 | 13,225 | 7.94 |
Separated | 330 | 3345 | 3675 | 8.98 |
Missing | 9935 | 118,450 | 128,385 | 7.74 |
Parity | ||||
0 | 41,025 | 546,435 | 587,460 | 6.98 |
1 | 23,890 | 405,325 | 429,215 | 5.57 |
2 | 15,775 | 213,305 | 229,080 | 6.89 |
Missing | 190 | 2300 | 2490 | 7.63 |
Maternal country of birth | ||||
Other | 33,855 | 500,350 | 534,205 | 6.34 |
Canada | 45,085 | 642,225 | 687,310 | 6.56 |
Missing | 1935 | 24,790 | 26,725 | 7.24 |
Infant sex | ||||
Male | 44,380 | 596,410 | 640,790 | 6.93 |
Female | 36,495 | 570,950 | 607,445 | 6.01 |
Missing | 5 | 5 | 10 | 50.00 |
City | ||||
St. John’s | 725 | 8570 | 9295 | 7.80 |
Saint John | 455 | 6760 | 7215 | 6.31 |
Fredericton | 335 | 4620 | 4955 | 6.76 |
Quebec | 2630 | 37,975 | 40,605 | 6.48 |
Trois Rivieres | 625 | 9690 | 10,315 | 6.06 |
Montreal | 11,350 | 170,830 | 182,180 | 6.23 |
Ottawa | 5110 | 76,605 | 81,715 | 6.25 |
Oshawa | 855 | 12,845 | 13,700 | 6.24 |
Toronto | 17,395 | 265,895 | 283,290 | 6.14 |
Mississauga | 4340 | 72,490 | 76,830 | 5.65 |
Brampton | 3695 | 52,325 | 56,020 | 6.60 |
Hamilton | 3205 | 44,960 | 48,165 | 6.65 |
St. Catharines | 690 | 11,390 | 12,085 | 5.71 |
Kitchener | 1370 | 21,600 | 22,970 | 5.96 |
Windsor | 1445 | 21,885 | 23,330 | 6.19 |
Winnipeg | 4965 | 64,845 | 69,810 | 7.11 |
Calgary | 8980 | 111,425 | 120,405 | 7.46 |
Edmonton | 6630 | 78,655 | 85,285 | 7.77 |
Richmond | 835 | 14,630 | 15,470 | 5.40 |
Vancouver | 3475 | 51,610 | 55,085 | 6.31 |
Victoria | 375 | 5805 | 6180 | 6.07 |
Nanaimo | 425 | 6385 | 6810 | 6.24 |
Kamloops | 440 | 6940 | 7385 | 5.96 |
Kelowna | 525 | 8620 | 9150 | 5.74 |
Birth year | ||||
1999 | 7660 | 113,210 | 120,875 | 6.34 |
2000 | 7980 | 113,205 | 121,185 | 6.58 |
2001 | 7810 | 115,315 | 123,130 | 6.34 |
2002 | 7750 | 113,460 | 121,210 | 6.39 |
2003 | 6880 | 100,615 | 107,495 | 6.40 |
2004 | 8115 | 115,690 | 123,805 | 6.55 |
2005 | 8365 | 118,735 | 127,100 | 6.58 |
2006 | 8505 | 122,110 | 130,615 | 6.51 |
2007 | 8720 | 125,625 | 134,340 | 6.49 |
2008 | 9090 | 129,395 | 138,485 | 6.56 |
Season | ||||
Spring (Apr-Jun) | 20,725 | 300,785 | 321,510 | 6.45 |
Summer (Jul-Sep) | 20,195 | 305,135 | 325,330 | 6.21 |
Autumn (Oct-Dec) | 19,850 | 280,030 | 299,880 | 6.62 |
Winter (Jan-Mar) | 20,110 | 281,415 | 301,525 | 6.67 |
Gestation (weeks) | ||||
20–27 | 4590 | 0 | 4590 | . |
28–31 | 6580 | 0 | 6580 | . |
32–33 | 8735 | 0 | 8735 | . |
34–36 | 60,970 | 0 | 60,970 | . |
37+ | 0 | 1,167,365 | 1,167,365 | . |
Total | 80,875 | 1,167,365 | 1,248,240 | 6.48 |
Total (excluding missing covariates) | 63,400 | 938,300 | 1,001,700 | 6.34 |
aIn accordance with Statistics Canada disclosure rules, case counts of less than five were suppressed, and all frequencies were randomly rounded to base five. As a result, there may be discrepancies between column totals and totals by infant/maternal characteristic. Statistical analyses employed unrounded data