Table 3

Relative risk (ORs with 95% CI) of cervical atypia (cytological SIL and/or CIN grade 1 or worse, CIN1+) associated with different covariables in analyses stratified by the interval between menarche and age at FSI (category 1), or between menarche and the age at start of OC (category 2) use in young adult women followed up for 4 years

VariableFrequency and relative risk of cytological atypia: SIL or CIN1 in the different categories by interval from menarche
Category 1Category 2
Menarche to FSI <3 years
SIL/CIN1+
Menarche to FSI ≥3 years
SIL/CIN1+
Menarche to start of OCs <3 years
SIL/CIN1+
Menarche to start of OCs ≥3 years
SIL/CIN1+
n/NOR (95% CI)n/NOR (95% CI)n/NOR (95% CI)n/NOR (95% CI)
HPV 16/18
 Positive21/1151.0 (0.6 to 2.0)45/1441.8 (1.1 to 2.7)13/691.4 (0.6 to 3.0)53/1901.4 (1.0 to 2.1)
 Negative33/186187/422118/1231102/4841
Chlamydia
 Positive14/541.8 (1.0 to 3.6)8/440.7 (0.3 to 1.6)10/392.2 (1.0 to 5.1)12/590.8 (0.4 to 1.6)
 Negative40/2481124/522121/1531143/6161
Smoking
 Yes34/1651.5 (0.8 to 2.7)52/2091.1 (0.8 to 1.7)22/1082.1 (1.0 to 5.0)64/2661.1 (0.8 to 1.6)
 No20/134180/35619/84191/4051
Condom use
 Yes22/1460.7 (0.4 to 1.2)59/2560.9 (0.6 to 1.3)15/1020.6 (0.3 to 1.3)66/3000.9 (0.6 to 1.3)
 No29/139161/251116/80174/3091
LNSPs
 High39/2151.1 (0.6 to 2.0)64/2451.3 (0.9 to 2.0)24/1351.5 (0.6 to 3.8)79/3251.2 (0.8 to 1.7)
 Low15/87168/32117/57176/3501
  • *Five or more.

  • CIN, cervical intraepithelial neoplasia; FSI, first sexual intercourse; LNSPs, lifetime number of sexual partners; OC, oral contraceptive; SIL, squamous intraepithelial lesion.