Table 3.
Associations of birth characteristics with childhood rhabdomyosarcoma
| Characteristic | Controls | Cases | ORa | 95% CI | p-value |
|---|---|---|---|---|---|
| Birth order, n (%) | |||||
| 1st | 138 (43.3) | 138 (43.4) | 1.00 | Reference | |
| 2nd | 101 (31.7) | 102 (32.1) | 0.94 | 0.64–1.37 | 0.731 |
| ≥3rd | 80 (25.1) | 78 (24.5) | 0.94 | 0.61–1.44 | 0.779 |
| Birth weightb, n (%) | |||||
| Normal (2,500g to <4,000g) | 267 (86.1) | 247 (77.7) | 1.00 | Reference | |
| LBW (<2,500g) | 10 (3.2) | 29 (9.1) | 1.69 | 0.71–4.01 | 0.236 |
| HBW (≥4,000g) | 33 (10.7) | 42 (13.2) | 1.35 | 0.77–2.37 | 0.287 |
| Length of pregnancyc, n (%) | |||||
| Normal | 258 (81.4) | 258 (81.1) | 1.00 | Reference | |
| Premature | 9 (2.8) | 26 (8.2) | 2.51 | 0.74–8.49 | 0.137 |
| Overdue | 50 (15.8) | 34 (10.7) | 0.70 | 0.41–1.18 | 0.177 |
| Type of delivery, n (%) | |||||
| Vaginal | 273 (85.8) | 260 (81.3) | 1.00 | Reference | |
| Cesarean | 45 (14.2) | 60 (18.8) | 1.44 | 0.90–2.31 | 0.132 |
| Paternal age (years) at child’s birth, mean (SD) | 29.0 (6.4) | 29.0 (5.9) | 0.99 | 0.96–1.02 | 0.395 |
| Maternal age (years) at child’s birth, mean (SD) | 26.3 (5.2) | 26.2 (5.2) | 0.99 | 0.96–1.02 | 0.435 |
OR = odds ratio; CI = confidence interval; LBW = low birth weight; HBW = high birth weight
a
Adjusted for sex, age, race, household income, and maternal and paternal education.
b
Adjusted for length of pregnancy
c
Adjusted for birth weight