Table 1.
Characteristics of participants.
| Mean ± SD or n (%) | ||||||||
|---|---|---|---|---|---|---|---|---|
| All | Having Cat(s) | Having Dog(s) | ||||||
| Parents | n = 78,868 | Yes (n = 6358) | No (n = 72,510) | p-Value | Yes (n = 11,934) | No (n = 66,934) | p-Value | |
| Maternal age at delivery (years) | 30.7 ± 5.1 | 30.8 ± 5.1 | 30.7 ± 5.1 | 0.832 | 30.6 ± 5.0 | 30.8 ± 5.1 | 0.034 | |
| Parity | nulliparous | 31,078 (39.4) | 2503 (39.4) | 28,575 (39.4) | 0.788 | 4721 (39.6) | 26,357 (39.4) | 0.754 |
| multipara | 32,986 (41.8) | 3720 (58.5) | 42,162 (58.1) | 6932 (58.1) | 38,950 (58.2) | |||
| missing | 1908 (2.4) | 135 (2.1) | 1773 (2.4) | 281 (2.4) | 1627 (2.4) | |||
| Maternal smoking at 2nd trimester | yes | 2874 (3.6) | 366 (5.7) | 2508 (3.5) | <0.001 | 641 (5.4) | 2233 (3.3) | <0.001 |
| no | 75,051 (95.2) | 5897 (92.7) | 69,154 (95.4) | <0.001 | 11,128 (93.2) | 63,923 (95.5) | <0.001 | |
| missing | 943 (1.2) | 95 (1.5) | 848 (1.2) | 165 (1.4) | 778 (1.2) | |||
| Maternal drinking at 2nd trimester | yes | 2134 (2.7) | 191 (3.0) | 1943 (2.7) | 0.123 | 336 (2.8) | 1798 (2.7) | 0.415 |
| no | 75,789 (96.1) | 6086 (95.7) | 69,703 (96.1) | 11,447 (95.9) | 64,342 (96.1) | |||
| missing | 945 (1.2) | 81 (1.3) | 864 (1.2) | 151 (1.3) | 794 (1.2) | |||
| Maternal education (years) | <13 | 26,859 (34.1) | 2781 (43.7) | 24,078 (33.2) | <0.001 | 4905 (41.1) | 21,954 (32.8) | <0.001 |
| ≥13 | 51,249 (65.0) | 3506 (55.1) | 47,743 (65.8) | 6889 (57.7) | 44,360 (66.3) | |||
| missing | 760 (1.0) | 71 (1.1) | 689 (1.0) | 140 (1.2) | 620 (0.9) | |||
| Paternal education (years) | <13 | 33,115 (42.0) | 3220 (50.6) | 29,895 (41.2) | <0.001 | 5940 (49.8) | 27,175 (40.6) | <0.001 |
| ≥13 | 44,570 (56.5) | 3003 (47.2) | 41,567 (57.3) | 5750 (48.2) | 38,820 (58.0) | |||
| missing | 1183 (1.5) | 135 (2.1) | 1048 (1.4) | 244 (2.0) | 939 (1.4) | |||
| Annual household income at 2nd trimester | <4 | 28,699 (36.4) | 2581 (40.6) | 26,118 (36.0) | <0.001 | 4440 (37.2) | 24,259 (36.2) | <0.001 |
| ≥4 | 44,361 (56.2) | 3115 (49.0) | 41,246 (56.9) | 6205 (52.0) | 38,156 (57.0) | |||
| missing | 5808 (7.4) | 662 (10.4) | 5146 (7.1) | 1289 (10.8) | 4519 (6.8) | |||
| Marital status | married | 74,783 (94.8) | 5952 (93.6) | 68,831 (94.9) | <0.001 | 11,167 (93.6) | 63,616 (95.0) | <0.001 |
| divorced/bereavement | 529 (0.1) | 72 (1.1) | 457 (0.6) | 149 (1.2) | 380 (0.6) | |||
| missing | 3556 (4.5) | 334 (5.3) | 3222 (4.4) | 618 (5.2) | 2938 (4.4) | |||
| Maternal possible mental illness | yes (K6 ≥ 13) | 2036 (2.6) | 234 (3.4) | 1802 (2.5) | <0.001 | 328 (2.7) | 1708 (2.6) | 0.205 |
| no (K6 < 13) | 76,156 (96.6) | 6067 (95.4) | 70,089 (96.7) | 11,493 (96.3) | 64,663 (96.6) | |||
| missing | 676 (0.8) | 57 (0.9) | 619 (0.9) | 113 (0.9) | 563 (0.8) | |||
| Infant | ||||||||
| Sex | male | 40,274 (51.1) | 3255 (51.2) | 37,019 (51.1) | 0.721 | 6095 (51.1) | 34,179 (51.1) | 0.994 |
| female | 38,572 (48.9) | 3100 (48.8) | 35,472 (48.9) | 5835 (48.9) | 32,737 (48.9) | |||
| missing | 22 (0.0) | 3 (0.0) | 19 (0.0) | 4 (0.0) | 18 (0.0) | |||
| Birth weight (g) | 3041 ± 384 | 3037 ± 383 | 3041 ± 384 | 0.428 | 3041 ± 386 | 3041 ± 383 | 0.926 | |
| Gestational age (weeks) | 39.4 ± 1.2 | 39.4 ± 1.2 | 39.4 ± 1.3 | 0.003 | 39.4 ± 1.2 | 39.4 ± 1.3 | 0.001 | |
| Delivery mode | vaginal | 64,007 (81.2) | 5157 (81.1) | 58,850 (81.2) | 0.796 | 9575 (80.2) | 54,432 (81.3) | 0.003 |
| cesarean | 14,665 (18.6) | 1191 (18.7) | 13,474 (18.6) | 2335 (19.6) | 12,330 (18.4) | |||
| missing | 196 (0.2) | 10 (0.2) | 186 (0.3) | 24 (0.2) | 172 (0.3) | |||
| Duration of breastfeeding (months) | 0 | 1978 (2.5) | 205 (3.2) | 1773 (2.4) | <0.001 | 346 (2.9) | 1632 (2.4) | <0.001 |
| 1–6 | 16,582 (21.0) | 1646 (25.9) | 14,936 (20.6) | 3000 (25.1) | 13,582 (20.3) | |||
| 7–12 | 60,308 (76.5) | 4507 (70.9) | 55,801 (77.0) | 8588 (72.0) | 51,720 (77.3) | |||
Missing data: n (%), maternal age: n = 93 (0.1), birth weight: n = 41 (0.05). Chi-square test or t-test.