Table 1 Demographics and clinical characteristics in the study groups
Characteristics | Normal cytology group (N=42,398) | CIN during pregnancy group (N=1380) | Treated group (N=3250) |
|---|---|---|---|
n (%) | n (%) | n (%) | |
Background factors adjusted for in the adjusted analyses | |||
Age at delivery (years) | |||
< 23 | 247 (0.6) | 17 (1.2) | 13 (0.4) |
23–30 | 24,485 (57.8) | 862 (62.5) | 1720 (52.9) |
31–38 | 16,438 (38.8) | 460 (33.3) | 1393 (42.9) |
>38 | 1228 (2.9) | 41 (3.0) | 124 (3.8) |
BMI class (kg/m2) | |||
Underweight (<18.5) | 874 (2.1) | 24 (1.7) | 73 (2.2) |
Normal-weight (18.5–24.9) | 23,957 (56.5) | 815 (59.1) | 1915 (58.9) |
Overweight (25–29.9) | 9144 (21.6) | 256 (18.6) | 654 (20.1) |
Obese (≥30) | 4110 (9.7) | 113 (8.2) | 287 (8.8) |
Missing | 4313 (10.2) | 172 (12.5) | 321 (9.9) |
Smoking | |||
Never | 34,969 (82.5) | 947 (68.6) | 2464 (75.8) |
Before pregnancy | 3063 (7.2) | 197 (14.3) | 346 (10.6) |
In early pregnancy only | 727 (1.7) | 40 (2.9) | 82 (2.5) |
In the third trimester | 1123 (2.6) | 107 (7.8) | 170 (5.2) |
Missing | 2516 (5.9) | 89 (6.4) | 188 (5.8) |
Infant’s sex | |||
Boy | 21,721 (51.2) | 728 (52.8) | 1646 (50.6) |
Girl | 20,676 (48.8) | 652 (47.2) | 1604 (49.4) |
Pregnant by assisted reproduction | |||
Yes | 1276 (3.0) | 15 (1.1) | 122 (3.8) |
Parity | |||
0 | 20,765 (49.0) | 801 (58.0) | 1964 (60.4) |
1–3 | 21,366 (50.4) | 568 (41.2) | 1269 (39.0) |
>3 | 267 (0.6) | 11 (0.8) | 17 (0.5) |
Marital status | |||
Cohabiting | 37,642 (88.8) | 1175 (85.1) | 2853 (87.8) |
Single | 494 (1.2) | 33 (2.4) | 53 (1.6) |
Other | 1149 (2.7) | 64 (4.6) | 97 (3.0) |
Missing | 3113 (7.3) | 108 (7.8) | 247 (7.6) |
Education levela | |||
Primary school, up to 9 years | 2785 (6.6) | 128 (9.3) | 218 (6.7) |
Secondary | 14,421 (34.0) | 618 (44.8) | 1246 (38.3) |
Post-secondary, <3 years | 5765 (13.6) | 207 (15.0) | 527 (16.2) |
Post-secondary, ≥3 years | 19,166 (45.2) | 413 (29.9) | 1250 (38.5) |
Missing | 261 (0.6) | 14 (1.0) | 9 (0.3) |
Country of birth | |||
Sweden | 35,031 (82.6) | 1183 (85.7) | 2948 (90.7) |
Europe | 3015 (7.1) | 102 (7.4) | 154 (4.7) |
Asia | 2908 (6.9) | 64 (4.6) | 96 (3.0) |
America/Oceania | 480 (1.1) | 14 (1.0) | 37 (1.1) |
Africa | 954 (2.3) | 17 (1.2) | 14 (0.4) |
Unknown/missing | 10 (0.0) | 0 | 1 (0.0) |
Year of delivery | |||
2008–2010 | 12,590 (29.7) | 308 (22.3) | 349 (10.7) |
2011–2013 | 12,831 (30.3) | 440 (31.9) | 1128 (34.7) |
2014–2016 | 16,977 (40.0) | 632 (45.8) | 1773 (54.6) |
Highest disposable household income, 3 years preceding delivery | |||
Lowest tertile | 6963 (16.4) | 267 (19.3) | 465 (14.3) |
Middle tertile | 13,503 (31.8) | 485 (35.1) | 1060 (32.6) |
Highest tertile | 21,932 (51.7) | 628 (45.5) | 1725 (53.1) |
Other background factors | |||
Employment | |||
Full-time | 22,135 (52.2) | 727 (52.7) | 1937 (59.6) |
Part-time | 9238 (21.8) | 273 (19.8) | 587 (18.1) |
None | 7003 (16.5) | 238 (17.2) | 387 (11.9) |
Missing | 4022 (9.5) | 142 (10.3) | 339 (10.4) |
Intercurrent diseaseb | |||
Renal disease | 140 (0.3) | 7 (0.5) | 12 (0.4) |
Diabetes | 204 (0.5) | 6 (0.4) | 11 (0.3) |
Epilepsy | 109 (0.3) | 4 (0.3) | 11 (0.3) |
Chronic hypertension | 84 (0.2) | 4 (0.3) | 8 (0.2) |
Gestational age estimated by | |||
Ultrasound | 38,911 (91.8) | 1266 (91.7) | 2997 (92.2) |
Last menstrual period | 505 (1.2) | 12 (0.9) | 31 (1.0) |
Otherc | 2982 (7.0) | 102 (7.4) | 222 (6.8) |