Table 1. Characteristics of 3 497 603 Pregnancies Among 2 211 789 Women, Overall and by Imaging Modality, US Sites and Ontario, Canadaa.
| Variable | Unique Pregnancies | Pregnancies by Imaging Modalityb | ||||
|---|---|---|---|---|---|---|
| Computed Tomography | Magnetic Resonance Imaging | Radiography | Fluoroscopy and Angiography | Nuclear Medicine | ||
| Pregnancies at US site | 3 497 603 | 16 267 (0.47) | 14 625 (0.42) | 122 174 (3.49) | 11 007 (0.31) | 6904 (0.20) |
| 1 | 23 217 (0.66) | 259 (1.12) | 139 (0.60) | 1853 (7.98) | 115 (0.50) | 80 (0.34) |
| 2 | 37 975 (1.09) | 220 (0.58) | 159 (0.42) | 3042 (8.01) | 72 (0.19) | 63 (0.17) |
| 3 | 77 541 (2.22) | 599 (0.77) | 487 (0.63) | 3316 (4.28) | 204 (0.26) | 151 (0.19) |
| 4 | 79 774 (2.28) | 670 (0.84) | 594 (0.74) | 4090 (5.13) | 314 (0.39) | 141 (0.18) |
| 5 | 101 513 (2.90) | 989 (0.97) | 1463 (1.44) | 4183 (4.12) | 459 (0.45) | 276 (0.27) |
| 6 | 587 814 (16.81) | 4038 (0.69) | 2334 (0.40) | 25 497 (4.34) | 1024 (0.17) | 653 (0.11) |
| Pregnancies in Ontario, Canada | 2 589 769 (74.04) | 9492 (0.37) | 9449 (0.36) | 80 193 (3.10) | 8819 (0.34) | 5540 (0.21) |
| Maternal age at start of pregnancy, y | 3 497 603 | 16 267 | 14 625 | 122 174 | 11 007 | 6904 |
| ≤19 | 188 451 (5.39) | 1239 (0.66) | 648 (0.34) | 9974 (5.29) | 629 (0.33) | 456 (0.24) |
| 20-29 | 1 572 292 (44.95) | 7792 (0.50) | 5974 (0.38) | 55 230 (3.51) | 4841 (0.31) | 3258 (0.21) |
| 30-39 | 1 647 359 (47.10) | 6720 (0.41) | 7399 (0.45) | 52 261 (3.17) | 5120 (0.31) | 2966 (0.18) |
| ≥40 | 89 501 (2.56) | 516 (0.58) | 604 (0.67) | 4709 (5.26) | 417 (0.47) | 224 (0.25) |
| Gestational age of neonate at birth, wkc | 3 497 603 | 16 267 | 14 625 | 122 174 | 11 007 | 6904 |
| 24-36 (Preterm) | 188 272 (5.38) | 1863 (0.99) | 2282 (1.21) | 10 310 (5.48) | 1287 (0.68) | 595 (0.32) |
| 37-40 (Full-term) | 2 973 888 (85.03) | 13 150 (0.44) | 11 329 (0.38) | 101 044 (3.40) | 9017 (0.30) | 5787 (0.19) |
| 41-43 (Late-term) | 335 443 (9.59) | 1254 (0.37) | 1014 (0.30) | 10 820 (3.23) | 703 (0.21) | 522 (0.16) |
| Year of neonate’s birth | 3 497 603 | 16 267 | 14 625 | 122 174 | 11 007 | 6904 |
| 1996-2000 | 756 497 (21.63) | 1888 (0.25) | 808 (0.11) | 25 765 (3.41) | 2950 (0.39) | 1126 (0.15) |
| 2001-2005 | 826 469 (23.63) | 3363 (0.41) | 2040 (0.25) | 28 992 (3.51) | 2427 (0.29) | 1638 (0.20) |
| 2006-2010 | 873 254 (24.97) | 4829 (0.55) | 4035 (0.46) | 29 974 (3.43) | 2393 (0.27) | 1847 (0.21) |
| 2011-2016 | 1 041 383 (29.77) | 6187 (0.59) | 7742 (0.74) | 37 443 (3.60) | 3237 (0.31) | 2293 (0.22) |
| Race of mother at US sitesd | 907 834 | 6775 | 5176 | 41 981 | 2188 | 1364 |
| White | 443 222 (48.82) | 3270 (0.74) | 2628 (0.59) | 19 679 (4.44) | 1171 (0.26) | 626 (0.14) |
| Asian | 166 867 (18.38) | 766 (0.46) | 521 (0.31) | 7955 (4.77) | 243 (0.15) | 174 (0.10) |
| Black | 55 056 (6.06) | 823 (1.49) | 356 (0.65) | 3683 (6.69) | 150 (0.27) | 126 (0.23) |
| Hawaiian/Pacific Islander | 14 620 (1.61) | 114 (0.78) | 65 (0.44) | 847 (5.79) | 34 (0.23) | 22 (0.15) |
| Native American | 5581 (0.61) | 65 (1.16) | 41 (0.73) | 329 (5.90) | 16 (0.29) | 9 (0.16) |
| Unknown | 222 488 (24.51) | 1737 (0.78) | 1565 (0.70) | 9488 (4.26) | 574 (0.26) | 407 (0.18) |
| Ethnicity of mother at US sitesd | 907 834 | 6775 | 4132 | 41 981 | 2188 | 1364 |
| Not Hispanic | 576 984 (63.56) | 4101 (0.71) | 2993 (0.52) | 26 699 (4.63) | 1289 (0.22) | 807 (0.14) |
| Hispanic | 172 658 (19.02) | 1384 (0.80) | 777 (0.45) | 8134 (4.71) | 319 (0.18) | 195 (0.11) |
| Unknown or not reported | 158 192 (17.43) | 1290 (0.82) | 362 (0.23) | 7148 (4.52) | 580 (0.37) | 362 (0.23) |
a
Data are number (%) of pregnancies.
b
Columns for receipt of imaging examination are not mutually exclusive of other imaging modalities.
c
If gestational age was missing, 40 weeks’ gestation was assumed.
d
Race and ethnicity information is not routinely collected in Ontario, Canada.