Table 1.
Child and family characteristics for children born in Sweden between 1 July 2005 and 30 September 2013 by antibiotic exposure
| Antibiotic exposure | ||||
|---|---|---|---|---|
| Prenatal life* | First year of life† | |||
| No | Yes | No | Yes | |
| Children, n | 566,141 | 164,098 | 607,636 | 189,682 |
| Parity, n (%) | ||||
| 1 | 253,677 (44.8) | 61,059 (37.2) | 284,118 (46.8) | 59,925 (31.6) |
| 2 | 209,774 (37.1) | 67,653 (41.2) | 217,512 (35.8) | 85,120 (44.9) |
| ≥3 | 102,690 (18.1) | 35,386 (21.6) | 106,006 (17.4) | 44,637 (23.5) |
| Mother’s BMI‡, median (IQR), kg/m2 | 23.6 (21.5, 26.6) | 23.9 (21.6, 27.3) | 23.5 (21.5, 26.6) | 23.9 (21.6, 27.1) |
| Missing | 23,211 (4.1) | 6,433 (3.9) | 27,098 (4.5) | 7,080 (3.7) |
| Cesarean delivery, n (%) | 91,491 (16.2) | 30,372 (18.5) | 99,694 (16.4) | 33,336 (17.6) |
| Elective before start of labor | 36,397 (6.4) | 13,410 (8.2) | 39,289 (6.5) | 14,966 (7.9) |
| Emergency | 53,887 (9.5) | 16,507 (10.1) | 58,948 (9.7) | 17,831 (9.4) |
| Missing | 1,207 (0.2) | 455 (0.3) | 1,457 (0.2) | 539 (0.3) |
| Type 1 diabetes, n (%) | ||||
| Mother | 3,292 (0.6) | 1,877 (1.1) | 4,133 (0.7) | 1,449 (0.8) |
| Father | 4,181 (0.7) | 1,319 (0.8) | 4,562 (0.8) | 1,417 (0.7) |
| Age at child’s birth, median (IQR), years | ||||
| Father | 33 (29, 37) | 33 (29, 37) | 33 (29, 37) | 33 (29, 37) |
| Mother | 30 (27, 34) | 31 (27, 34) | 30 (27, 34) | 31 (27, 34) |
| Mother born in Sweden, n (%) | 461,051 (81.4) | 132,739 (80.9) | 501,097 (82.5) | 149,730 (78.9) |
| Father born in Sweden, n (%) | 459,694 (81.2) | 130,998 (79.8) | 500,078 (82.3) | 147,370 (77.7) |
| Girls, n (%) | 274,825 (48.5) | 79,843 (48.7) | 303,342 (49.9) | 83,988 (44.3) |
| Gestational age (weeks), n (%) | ||||
| <38 | 51,469 (9.1) | 17,599 (10.7) | 56,181 (9.2) | 18,519 (9.8) |
| 38 | 77,073 (13.6) | 24,961 (15.2) | 83,098 (13.7) | 28,395 (15.0) |
| 39–40 | 296,155 (52.3) | 83,327 (50.8) | 315,667 (52.0) | 97,935 (51.6) |
| ≥41 | 141,444 (25.0) | 38,211 (23.3) | 152,512 (25.1) | 44,779 (23.6) |
| Missing | 0 (0.0) | 0 (0.0) | 178 (<0.1) | 54 (<0.1) |
| Birth weight, n (%) | ||||
| Small for gestational age | 11,693 (2.1) | 3,335 (2.0) | 12,671 (2.1) | 3,571 (1.9) |
| Normal | 534,206 (94.4) | 153,740 (93.7) | 573,158 (94.3) | 177,851 (93.8) |
| Large for gestational age | 19,533 (3.5) | 6,788 (4.1) | 20,890 (3.4) | 7,957 (4.2) |
| Missing | 709 (0.1) | 235 (0.1) | 917 (0.2) | 303 (0.2) |
IQR, interquartile range.
*
Children from pregnancies with an estimated start date on or after 1 July 2005. At least one antibiotic prescription during estimated duration of pregnancy.
†
At least one dispensed antibiotic prescription in the child’s 1st year of life.
‡
At the first visit at the antenatal clinic.