Table 3

 Comparison of patients with pelvic inflammatory disease with tubal ligation control group: unadjusted ORs, adjusted ORs (95% CIs)

VariablePatients n = 140 n (%)Controls n = 105 n (%)Adjusted OR(95% CI)p Value
LCR, ligase chain reaction; MIF, microimmunofluorescence; STI, sexually transmitted infection.
*Standard occupational classification 2000: 1, managers and senior officials; professional; associate professional and technical; 2, administrative and secretarial; skilled trades; 3, personal service; sales, customer service; 4, process, plant and machine operatives; elementary; 5, unknown.14
†Coil, cap and injection (Depo-Provera).
‡Stillbirth, miscarriage and ectopic pregnancy.
§Combined results of nucleic acid amplification, serological and heat shock protein 60 (CHSP60) tests. Yes, LCR positive, MIF positive or CHSP60 positive; no, LCR negative, MIF negative and CHSP60 negative.
Age group (years)0.008
    16–2477 (55)7 (7)6.52 (1.86 to 22.82)
    25–3448 (34)57 (54)1
    ⩾3515 (11)41 (39)1.28 (0.41 to 4.01)
Age at first sexual intercourse0.013
    <1524 (17)6 (6)0.91 (0.20 to 4.11)
    15–19113 (81)84 (80)1
    ⩾203 (2)15 (14)0.04 (0.003 to 0.58)
Lifetime sexual partners0.7553
    1–470 (50)69 (66)1
    ⩾570 (50)36 (34)0.86 (0.33 to 2.23)
Ethnicity0.0297
    White125 (89)104 (99)1
    Other15 (11)1 (1)15.30 (0.73 to 318.87)
Socioeconomic status*0.8663
    122 (16)8 (8)1
    218 (13)18 (17)0.58 (0.09 to 3.74)
    353 (38)48 (46)0.67 (0.13 to 3.39)
    47 (5)16 (15)0.57 (0.08 to 4.13)
    540 (28)15 (14)0.27 (0.06 to 2.39)
Children<0.001
    Yes68 (49)101 (96)0.05 (0.01 to 0.25)
    No72 (51)4 (4)1
Contraception0.14
    Condom (1)42 (30)36 (34)1
    Oral (2)40 (29)26 (25)2.54 (0.78 to 8.24)
    Other† (3)34 (24)19 (18)3.63 (1.11 to 11.87)
    None (4)24 (17)24 (23)1.64 (0.43 to 6.16)
Marital status0.172
    Married (1)11 (8)43 (41)1
    Cohabiting (2)31 (22)27 (26)2.37 (0.63 to 8.97)
    Widowed/separated/divorce (3)18 (13)13 (12)3.85 (0.90 to 16.55)
    Single (4)80 (57)22 (21)3.69 (0.98 to 13.90)
Smoker0.503
    Yes86 (61)58 (55)1.38 (0.54 to 3.52)
    No54 (39)47 (45)1
Termination of pregnancy0.323
    Yes41 (29)40 (38)0.63 (0.25 to 1.59)
    No99 (71)65 (62)1
Adverse pregnancy outcome‡0.711
    Yes26 (19)31 (30)0.83 (0.30 to 2.28)
    No114 (81)74 (70)1
History of an STI<0.001
    Yes82 (59)11 (10)10.14 (3.52 to 29.17)
    No58 (41)94 (90)1
Exposure to C trachomatis§0.02
    Yes42 (30)8 (8)5.17 (1.19 to 22.51)
    No98 (70)97 (92)1