Table 1.
Distribution of background characteristics
| Characteristic | MoBa (n = 81 630) | DNBC (n = 50 701) |
|---|---|---|
| Maternal age [mean (SD)] | 30.2 (4.5) | 30.6 (4.2) |
| Maternal parity [n (%)] | ||
| Primiparous | 37 413 (45.8) | 23 061 (45.5) |
| 1 | 28 731 (35.2) | 19 004 (37.5) |
| 2+ | 15 486 (19.0) | 8621 (17.0) |
| Missing | 0 (0.0) | 15 (0.03) |
| Maternal education [n (%)] | ||
| Less than high school (MoBa)/9th grade with exam (DNBC) | 5579 (6.8) | 3672 (7.2) |
| High school (MoBa)/10th grade with exam (DNBC) | 23 452 (28.7) | 13 687 (27.0) |
| Up to 4 years of college (MoBa)/Technical school (DNBC) | 33 680 (41.3) | 6886 (13.6) |
| More than 4 years of college (MoBa)/ High school or more (DNBC) | 18 576 (22.8) | 25 969 (51.2) |
| Missing | 343 (0.4) | 507 (1.0) |
| Maternal smoking during pregnancy [n (%)] | ||
| No | 62 963 (77.1) | 37 954 (74.9) |
| Yes | 18 346 (22.5) | 12 746 (25.1) |
| Missing | 321 (0.4) | 1 (0.0) |
| Maternal diabetes [n (%)]a | ||
| No | 81 268 (99.6) | 49 316 (97.3) |
| Yes | 362 (0.4) | 1385 (2.7) |
| Maternal pre-pregnancy body mass index [n (%)] | ||
| Underweight | 2363 (2.9) | 2066 (4.1) |
| Normal weight | 52 433 (64.2) | 33 614 (66.3) |
| Overweight | 17 474 (21.4) | 9996 (19.7) |
| Obese | 7375 (9.0) | 4211 (8.3) |
| Missing | 1985 (2.4) | 814 (1.6) |
| Maternal gestational weight gain [mean (SD)] | 14.9 (5.8) | 14.9 (5.9) |
| Missing [n (%)] | 6096 (7.5) | 529 (1.0) |
| Paternal age [n (%)] | ||
| Less than 25 | 3566 (4.4) | 1656 (3.3) |
| 25–29 | 18 446 (22.6) | 13 184 (26.0) |
| 30–34 | 31 934 (39.1) | 20 011 (39.5) |
| 35+ | 27 492 (33.7) | 15 232 (30.0) |
| Missing | 192 (0.2) | 618 (1.2) |
| Paternal education [n (%)] | ||
| Less than high school (MoBa)/9th grade with exam (DNBC) | 8026 (9.8) | 9430 (18.6) |
| High school (MoBa)/10th grade with exam (DNBC) | 31 845 (39.0) | 17 608 (34.7) |
| Up to 4 years of college (MoBa)/Technical school (DNBC) | 21 728 (26.6) | 2784 (5.5) |
| More than 4 years of college (MoBa)/ High school or more (DNBC) | 17 609 (21.6) | 18 928 (37.3) |
| Missing | 2422 (3.0) | 1951 (3.8) |
| Paternal smoking (MoBa)/Partner smoking (DNBC) [n (%)] | ||
| No | 59 930 (73.4) | 35 827 (70.7) |
| Yes | 21 301 (26.1) | 14 834 (29.3) |
| Missing | 399 (0.5) | 40 (0.1) |
| Paternal type 1 diabetes [n (%)] | ||
| No | 81 106 (99.4) | NA |
| Yes | 524 (0.6) | NA |
| Paternal pre-pregnancy body mass index [n (%)] | ||
| Underweight | 163 (0.2) | 191 (0.4) |
| Normal weight | 34 971 (42.8) | 25 499 (50.3) |
| Overweight | 35 313 (43.3) | 19 274 (38.0) |
| Obese | 7544 (9.2) | 3475 (6.8) |
| Missing | 3639 (4.5) | 2262 (4.5) |
| Child gender [n (%)] | ||
| Male | 41 796 (51.2) | 25 773 (50.8) |
| Female | 39 834 (48.8) | 24 928 (49.2) |
| Child birth weight [mean (SD)] | 3.6 (0.5) | 3.6 (0.5) |
| Missing | 99 (0.1) | 251 (0.5) |
| Child weight gain the first year of life in kg [mean (SD)] | 6.3 (1.0) | 6.6 (1.1) |
| Missing | 21 430 (26.3) | 9403 (18.5) |
| Child type 1 diabetes [n (%)] | ||
| No | 81 337 (99.6) | 50 495 (99.6) |
| Yes | 293 (0.4) | 206 (0.4) |
| Child age at type 1 diabetes diagnosis [median (range)] | 7.1 (0.7, 15.0) | 9.6 (0.9, 17.0) |
a
Maternal diabetes includes only type 1 diabetes in MoBa whereas it includes all forms of diabetes in DNBC.