TABLE 2.
RRs and 95% CI for Selected Associations in Danish Medical Birth Registry Data, Among Snart Gravid Study Participants and Among All Danish Births, 2008–2012
| Snart Gravid N = 4,801
|
Danish Medical Birth Registry N = 239,791
|
|||||
|---|---|---|---|---|---|---|
| N | Crude RR | Adjusted RR (95% CI) | N | Crude RR | Adjusted RR (95% CI) | |
| Smoking and birth weight <3,000 ga | ||||||
| Current smoker | 90 | 1.8 | 1.8 (1.5, 2.3) | 7,554 | 1.8 | 1.8 (1.7, 1.8) |
| Nonsmoker | 591 | 1.00 (ref) | 1.00 (ref) | 27,402 | 1.00 (ref) | 1.00 (ref) |
| Quit during pregnancy | 15 | 1.3 | 1.2 (0.7, 1.9) | 1,073 | 1.1 | 1.1 (1.00, 1.1) |
| Current smoker 1–10 cigarettes/day | 46 | 1.8 | 1.9 (1.4, 2.5) | 4,245 | 1.9 | 1.9 (1.8, 1.9) |
| Current smoker >10 cigarettes/day | 26 | 2.3 | 2.6 (1.8, 3.6) | 2,077 | 2.2 | 2.3 (2.2, 2.4) |
| Smoking and birth weight <2,500 ga | ||||||
| Current smoker | 18 | 1.5 | 1.4 (0.8, 2.4) | 2,004 | 2.0 | 2.1 (2.0, 2.2) |
| Nonsmoker | 143 | 1.00 (ref) | 1.00 (ref) | 6,390 | 1.00 (ref) | 1.00 (ref) |
| Quit during pregnancy | 4 | 1.43 | 1.1 (0.4, 3.3) | 275 | 1.2 | 1.2 (1.1, 1.3) |
| Current smoker 1–10 cigarettes/day | 6 | 1.0 | 1.1 (0.5, 2.5) | 1,095 | 2.0 | 2.2 (2.0, 2.3) |
| Current smoker >10 cigarettes/day | 8 | 3.0 | 2.7 (1.2, 5.9) | 584 | 2.6 | 2.9 (2.6, 3.1) |
| Parity and pre-eclampsiab | ||||||
| Nulliparous | 223 | 1.6 | 1.7 (1.3, 2.3) | 8,264 | 2.0 | 2.3 (2.2, 2.4) |
| Primiparous | 51 | 1.00 (ref) | 1.00 (ref) | 2,212 | 1.00 (ref) | 1.00 (ref) |
| Prior C-section and C-sectionc | ||||||
| No prior C-section | 856 | 1.00 (ref) | 1.00 (ref) | 37,421 | 1.00 (ref) | 1.00 (ref) |
| Prior C-section | 168 | 3.7 | 4.9 (4.0, 6.1) | 11,447 | 3.9 | 5.0 (4.9, 5.2) |
| Maternal BMI and macrosomia >4,000 gd | ||||||
| BMI < 20 | 61 | 0.67 | 0.66 (0.51, 0.86) | 3,148 | 0.62 | 0.64 (0.62, 0.66) |
| 20–24 | 341 | 1.00 (ref) | 1.00 (ref) | 17,323 | 1.00 (ref) | 1.00 (ref) |
| 25–29 | 203 | 1.4 | 1.3 (1.1, 1.6) | 9,187 | 1.3 | 1.3 (1.25, 1.31) |
| ≥30 | 130 | 1.5 | 1.5 (1.2, 1.7) | 6,253 | 1.5 | 1.5 (1.45, 1.53) |
| Maternal BMI and pre-eclampsiac | ||||||
| BMI < 20 | 26 | 0.95 | 0.88 (0.56, 1.37) | 916 | 0.69 | 0.70 (0.65, 0.75) |
| 20–24 | 102 | 1.00 (ref) | 1.00 (ref) | 4,372 | 1.00 (ref) | 1.00 (ref) |
| 25–29 | 72 | 1.8 | 1.8 (1.4, 2.5) | 2,619 | 1.5 | 1.6 (1.5, 1.7) |
| ≥30 | 73 | 3.0 | 3.0 (2.3, 4.0) | 2,522 | 2.6 | 2.7 (2.6, 2.8) |
| Maternal BMI and C-sectionc | ||||||
| BMI < 20 | 113 | 0.89 | 0.90 (0.75, 1.09) | 5,705 | 0.86 | 0.89 (0.86, 0.91) |
| 20–24 | 479 | 1.00 (ref) | 1.00 (ref) | 22,563 | 1.00 (ref) | 1.00 (ref) |
| 25–29 | 228 | 1.2 | 1.2 (1.0, 1.4) | 11,344 | 1.2 | 1.3 (1.2, 1.3) |
| ≥30 | 182 | 1.5 | 1.6 (1.3, 1.8) | 8,392 | 1.6 | 1.6 (1.56, 1.63) |
a
Adjusted for parity, maternal age, BMI.
b
Adjusted for smoking, maternal age, BMI.
c
Adjusted for smoking, parity, maternal age, BMI.
d
Adjusted for smoking, parity, maternal age.