Table 3

ORsa and 95% CIs for use of OCs among adenocarcinoma cases and squamous cell carcinoma cases, stratified by in situ versus invasive tumors

AdenocarcinomasSquamous cell carcinomas
In situInvasiveIn situInvasive
nbOR (95% CI)nbOR (95% CI)nbOR (95% CI)nbOR (95% CI)
Never used OCs21.0 (ref)c211.0 (ref)c71.0 (ref)c271.0 (ref)c
Ever used OCs313.4 (0.7–16.0)700.8 (0.4–1.6)411.0 (0.4–2.8)640.8 (0.4–1.7)
 Former use132.0 (0.4–9.9)570.8 (0.4–1.5)321.3 (0.5–3.6)530.9 (0.4–1.7)
 Current used1812.6 (2.5–64.2)100.6 (0.2–2.0)90.9 (0.2–3.3)100.9 (0.3–2.6)
Duration of use
 2 years or less73.2 (0.6–17.2)200.8 (0.3–1.8)100.9 (0.3–3.0)230.9 (0.4–2.0)
 2–6 years71.7 (0.3–9.5)210.7 (0.3–1.6)150.9 (0.3–2.8)180.7 (0.3–1.6)
 >6 years176.0 (1.2–30.7)260.8 (0.3–1.8)161.2 (0.4–3.9)220.9 (0.4–2.2)
P (trend)P = 0.03P = 0.62P = 0.67P = 0.74
Age at first OC use
 Before 17134.6 (0.9–23.9)190.7 (0.3–1.9)110.7 (0.2–2.6)211.2 (0.4–3.0)
 18 or 1984.1 (0.7–22.8)170.8 (0.3–2.1)161.6 (0.5–5.0)161.1 (0.4–2.8)
 20–2252.2 (0.4–13.1)210.9 (0.4–2.2)91.0 (0.3–3.4)170.9 (0.3–2.2)
 After 2252.9 (0.5–17.1)130.7 (0.3–1.7)50.9 (0.2–3.5)100.5 (0.2–1.4)
P (trend)P = 0.86P = 0.59P = 0.86P = 0.19
  • a Adjusted for age, ethnicity, income, HPV, lifetime number of sexual partners, and number of Pap smears.

  • b Excludes missing responses.

  • c Referent group for the column.

  • d Defined as OC use 12 months before diagnosis for cases and at reference date for controls.