Table 4

Hormonal and reproductive factors and polyp risks

Controls n (%)Cases with hyperplastic polyps (n = 97)Cases with adenomatous polyps (n = 173)Cases with both types of polyps (n = 46)
Cases n (%)Age-adjustedMultivariate-adjustedCases n (%)Age-adjustedMultivariate-adjustedCases n (%)Age-adjustedMultivariate-adjusted
OR95% CIORa95% CIaOR95% CIORa95% CIaOR95% CIORa95% CIa
Ever use HRT
 No206 (49)54 (57)1.01.0103 (61)1.01.024 (54)1.01.0
 Yes218 (51)40 (43)0.60.4–1.00.70.4–1.165 (39)0.50.3–0.70.50.3–0.720 (46)0.60.3–1.10.70.3–1.2
P0.040.09<0.001<0.0010.110.19
Ever use oral contraceptives
 No170 (39)44 (46)1.01.084 (49)1.01.022 (48)1.01.0
 Yes261 (61)52 (54)0.90.5–1.40.90.5–1.587 (51)1.00.6–1.41.20.8–1.924 (52)1.60.8–3.31.90.9–4.1
P0.430.670.790.450.200.08
Parity
 066 (15)14 (14)1.01.021 (12)1.01.07 (15)1.01.0
 1 or 2152 (35)35 (36)1.10.5–2.11.10.5–2.366 (38)1.40.8–2.51.40.8–2.611 (24)0.70.3–1.90.70.3–2.0
 3 or 4157 (36)36 (37)1.00.5–1.91.00.5–2.156 (32)0.70.5–1.70.90.5–1.619 (41)0.90.3–2.20.80.3–2.0
 5 or more64 (14)12 (12)0.70.3–1.70.70.3–1.730 (17)1.00.5–2.01.00.5–2.19 (20)0.80.3–2.40.60.2–1.8
P0.430.450.430.400.910.41
Age at first live birth
 <2087 (23)22 (26)1.01.026 (17)1.01.08 (20)1.01.0
 20–24177 (48)34 (41)0.70.4–1.30.70.4–1.480 (53)1.30.8–2.31.40.8–2.422 (56)1.00.4–2.51.10.4–2.7
 25–2978 (21)22 (26)1.10.6–2.21.40.7–2.836 (24)1.50.8–2.71.70.9–3.27 (18)0.80.3–2.51.10.4–3.5
 30 or older31 (8)5 (6)0.70.2–1.90.60.2–1.810 (7)1.00.4–2.31.10.5–2.82 (5)0.60.1–2.90.70.1–3.8
P0.910.970.590.360.490.86
  • a Multivariate adjustment for age, BMI, HRT (yes/no), smoking (pack-years), and alcohol, where appropriate.