Table 3 Breast cancer odds ratio (ORs) in relation to participant’s perinatal exposures, excluding in situ cases
From: Perinatal and postnatal exposures and risk of young-onset breast cancer
Characteristics | Controls (n = 1467) | Cases (n = 1250) | OR (95% CI) | OR (95% CI) |
|---|---|---|---|---|
Preeclampsia/eclampsia/toxemia | n (%) | n (%) | ||
No | 990 (98.5) | 867 (97.6) | 1.00 | 1.00 |
Yes | 15 (1.5) | 21 (2.4) | 2.87 (1.08–7.59)¥ | 4.03 (1.29–12.6)€ |
Gestational hypertension§ | ||||
No | 958 (97.5) | 818 (97.7) | 1.00 | 1.00 |
Yes | 25 (2.5) | 19 (2.3) | 0.91 (0.46–1.80) | 1.00 (0.49–2.04)€ |
Any hypertensive disorder | ||||
No | 984 (96.1) | 867 (98.6) | 1.00 | 1.00 |
Yes | 40 (3.9) | 40 (4.4) | 1.32 (0.75–2.32)¥ | 1.58 (0.85–2.92)€ |
Maternal smoking | ||||
No | 787 (70.5) | 692 (70.3) | 1.00 | |
Yes | 329 (29.5) | 292 (29.7) | 1.13 (0.75–1.70)* | |
Low birth weight | ||||
Birth weight > 5.5 pounds | 1033 (93.3) | 907 (92.3) | 1.00 | 1.00 |
Birth weight ≤5.5 pounds | 74 (6.7) | 76 (7.7) | 1.17 (0.78–1.74) | 1.14 (0.71–1.81)Ŧ |
High birth weight | ||||
Birth weight < 8.8 pounds | 741 (91.8) | 642 (89.4) | 1.00 | 1.00 |
Birth weight ≥ 8.8 pounds | 66 (8.2) | 76 (10.6) | 1.67 (1.10–2.54) | 1.52 (0.96–2.40)Ŧ |
Breastfed | ||||
No | 664 (60.2) | 611 (62.7) | 1.00 | |
Yes | 438 (39.8) | 364 (37.3) | 0.80 (0.60–1.07) | |
Soy-fed (formula made from soy) | ||||
No | 847 (95.6) | 743 (95.5) | 1.00 | |
Yes | 39 (4.4) | 35 (4.5) | 0.92 (0.56–1.52) | |
DES exposure during pregnancy | ||||
No | 872 (96.8) | 776 (97.1) | 1.00 | |
Yes | 29 (3.2) | 23 (2.9) | 0.85 (0.44–1.65) | |
Short gestational length at birth | ||||
Born ≥ 38 weeks | 474 (87.8) | 412 (84.6) | 1.00 | 1.00 |
Born < 38 weeks | 66 (12.2) | 75 (15.4) | 1.38 (0.90–2.11) | 1.28 (0.81–2.02)Ŧ |