Table 1:
Sociodemographic characteristics, perinatal health services contact, and vaccination information among patients in the primary birth cohorts
| Variable | No. (%)* | |||
|---|---|---|---|---|
| Overall n = 86 815 |
2019 birth group n = 29 181 |
2021 birth group n = 29 258 |
2022 birth group n = 28 376 |
|
| Sociodemographic characteristics | ||||
| Age, yr, median (IQR) | 32 (28–35) | 31 (28–35) | 31 (28–35) | 32 (29–35) |
| Rural residence | 6202 (7.1) | 2094 (7.2) | 2066 (7.1) | 2042 (7.2) |
| Neighbourhood-level ethnocultural composition† | ||||
| 1 (least diversity) | 13 533 (15.6) | 4556 (15.6) | 4604 (15.7) | 4373 (15.4) |
| 2 | 13 997 (16.1) | 4600 (15.8) | 4795 (16.4) | 4602 (16.2) |
| 3 | 15 527 (17.9) | 5128 (17.6) | 5211 (17.8) | 5188 (18.3) |
| 4 | 19 044 (21.9) | 6387 (21.9) | 6361 (21.7) | 6296 (22.2) |
| 5 (greatest diversity) | 24 714 (28.5) | 8510 (29.2) | 8287 (28.3) | 7917 (27.9) |
| Neighbourhood-level economic dependency† | ||||
| 1 (least dependency) | 24 963 (28.8) | 8340 (28.6) | 8435 (28.8) | 8188 (28.9) |
| 2 | 18 099 (20.8) | 5980 (20.5) | 6162 (21.1) | 5957 (21.0) |
| 3 | 16 161 (18.6) | 5519 (18.9) | 5278 (18.0) | 5364 (18.9) |
| 4 | 14 839 (17.1) | 5001 (17.1) | 5055 (17.3) | 4783 (16.9) |
| 5 (greatest dependency) | 12 753 (14.7) | 4341 (14.9) | 4328 (14.8) | 4084 (14.4) |
| Neighbourhood-level residential instability† | ||||
| 1 (least instability) | 12 601 (14.5) | 4190 (14.4) | 4353 (14.9) | 4058 (14.3) |
| 2 | 16 387 (18.9) | 5374 (18.4) | 5604 (19.2) | 5409 (19.1) |
| 3 | 19 047 (21.9) | 6425 (22.0) | 6311 (21.6) | 6311 (22.2) |
| 4 | 18 645 (21.5) | 6159 (21.1) | 6274 (21.4) | 6212 (21.9) |
| 5 (greatest instability) | 20 135 (23.2) | 7033 (24.1) | 6716 (23.0) | 6386 (22.5) |
| Perinatal health services contact | ||||
| Use of assisted reproductive technology for current pregnancy | 3061 (3.5) | 1128 (3.9) | 595 (2.0) | 1338 (4.7) |
| Early prenatal care visits (count), median (IQR)‡ | 5 (3–7) | 6 (4–8) | 5 (3–7) | 5 (3–7) |
| Prenatal care provider type | ||||
| Obstetrician | 56 717 (65.3) | 18 931 (64.9) | 19 330 (66.1) | 18 456 (65.0) |
| Family physician | 12 308 (14.2) | 4459 (15.3) | 3966 (13.6) | 3883 (13.7) |
| Shared care§ | 2280 (2.6) | 741 (2.5) | 758 (2.6) | 781 (2.8) |
| Midwife | 14 372 (16.6) | 4761 (16.3) | 4794 (16.4) | 4817 (17.0) |
| No care or other | 1138 (1.3) | 289 (1.0) | 410 (1.4) | 439 (1.5) |
| Parity | ||||
| 0 | 37 846 (43.6) | 12 390 (42.5) | 12 973 (44.3) | 12 483 (44.0) |
| 1 | 31 365 (36.1) | 10 737 (36.8) | 10 416 (35.6) | 10 212 (36.0) |
| 2 | 11 276 (13.0) | 3874 (13.3) | 3747 (12.8) | 3655 (12.9) |
| ≥ 3 | 6328 (7.3) | 2180 (7.5) | 2122 (7.3) | 2026 (7.1) |
| ≥ 1 infant(s) aged ≤ 24 mo in household | 11 433 (13.2) | 3882 (13.3) | 3824 (13.1) | 3727 (13.1) |
| SARS-CoV-2 vaccination (2022 birth group only) | ||||
| First dose | ||||
| Overall¶ | – | – | – | 22 581 (79.6) |
| Timing | ||||
| Before conception | – | – | – | 11 264 (49.9) |
| During pregnancy | – | – | – | 10 435 (46.2) |
| After giving birth | – | – | – | 882 (3.9) |
| Second dose | ||||
| Overall§ | – | – | – | 21 425 (75.5) |
| Timing | ||||
| Before conception | – | – | – | 2929 (13.7) |
| During pregnancy | – | – | – | 17 595 (82.1) |
| After giving birth | – | – | – | 901 (4.2) |
| SARS-CoV-2 and Tdap vaccination (2022 birth group only) | ||||
| Received dose 1 and Tdap vaccine | – | – | – | 8347 (29.4) |
| Received dose 1 but not Tdap vaccine | – | – | – | 14 234 (50.2) |
| Received Tdap vaccine but not dose 1 | – | – | – | 916 (3.2) |
| Received neither Tdap vaccine nor dose 1 | – | – | – | 4879 (17.2) |
| Received dose 2 and Tdap vaccine | – | – | – | 8086 (28.5) |
| Received dose 2 but not Tdap vaccine | – | – | – | 13 339 (47.0) |
| Received Tdap vaccine but not dose 2 | – | – | – | 1177 (4.1) |
| Received neither Tdap vaccine nor dose 2 | – | – | – | 5774 (20.3) |
| Tdap and influenza vaccination | ||||
| Received both Tdap and influenza vaccine | 12 877 (14.8) | 3734 (12.8) | 5186 (17.7) | 3957 (13.9) |
| Received influenza but no Tdap vaccine | 13 676 (15.8) | 4614 (15.8) | 5152 (17.6) | 3910 (13.8) |
| Received Tdap but no influenza vaccine | 12 046 (13.9) | 2742 (9.4) | 3998 (13.7) | 5306 (18.7) |
| Received neither influenza nor Tdap vaccine | 48 216 (55.5) | 18 091 (62.0) | 14 922 (51.0) | 15 203 (53.6) |
Note: IQR = interquartile range; Tdap = tetanus, diphtheria and pertussis.
*
Unless stated otherwise.
†
Measured as quintiles.
‡
Early prenatal care visits occurred before 32 weeks of gestation.
§
Includes patients with an equal number of minor prenatal assessment billings by family physicians and obstetricians between conception date and index date.
¶
Vaccine records were examined for each birthing person between Dec. 1, 2020, and up to June 30, 2022.