Table 1

Association of selected background variables with the risk of ovarian cancer

BackgroundCasesControlsORa95% CI
No.(%)No.(%)
Total129(100)144(100)
Age
 ≤4435(27)36(25)
 45–5232(25)40(28)
 53–6528(22)37(26)
 >6534(26)31(21)
Ethnic group
 Caucasian36(28)42(29)
 Asian58(45)69(48)
 Other35(27)33(23)
Education (years)
 ≤1247(36)35(24)1b
 13–1447(36)49(34)0.70.4–1.3
 1519(15)35(24)0.40.2–0.8
 >1516(12)25(18)0.50.2–1.1
Pregnancy
 Never25(19)17(12)1b
 Ever104(81)127(88)0.50.3–1.0
Oral contraceptive pill use
 Never78(60)46(32)1b
 Ever51(40)98(68)0.20.1–0.4
Tubal ligation
 Never110(85)107(74)1b
 Ever19(15)37(26)0.50.3–0.9
Menstrual periods
 Regular97(75)92(64)1b
 Irregular32(25)52(36)0.60.3–1.0
Tobacco smoking
 Never77(60)97(67)1b
 Ever52(40)47(33)1.40.8–2.3
  • a Adjusted by multiple unconditional logistic regression for age and ethnicity.

  • b Reference category.