Table 1.

Baseline characteristics of 180 premenopausal women with invasive (n = 170) or in situ (n = 10) breast cancer and their 683 matched controls

All womenCases (n = 180)Controls (n = 683)
Age, y43.4 (4.3)43.1 (4.3)
Urinary aMT6s, ng/mL creatinine29.3 (1.11)27.6 (0.57)
Urinary aMT6s/12 h, μg17.4 (0.61)15.8 (0.31)
Age at menarche, y12.6 (1.4)12.6 (1.4)
Parity (among parous women only; %)1.9 (0.8)2.0 (0.8)
Age at first birth (among parous women only)22.8 (9.4)22.7 (9.0)
Family history of breast cancer (%)9.47.6
OC use (%)45.341.9
BMI, kg/m224.3 (4.4)24.4 (4.0)
Alcohol consumption, g/d9.4 (13.0)8.8 (12.8)
History of benign breast disease (%)31.127.2
Education beyond 8 y of elementary school (%)41.731.7
Smoking history
    Current smoker (%)20.024.5
    Past smoker (%)20.012.5
    Never smoker (%)60.063.0
    Pack-years among ever smokers9.6 (9.0)9.4 (10.1)
Sex hormone levels
    SHBG (nmol/L)65.7 (2.1)67.3 (1.1)
    Testosterone (ng/mL)0.29 (0.01)0.28 (0.06)
    Free testosterone (pg/mL)0.71 (0.03)0.69 (0.02)
    Estradiol (pg/mL)90.8 (3.9)95.3 (2.0)
    FSH (μg/mL)4.1 (0.12)4.0 (0.06)
    LH (μg/mL)2.5 (0.14)2.7 (0.07)

NOTE: Mean (SD) of Baseline characteristics of 180 premenopausal women was shown and their 683 controls.

Abbreviation: OC, oral contraceptive; FSH, follicle-stimulating hormone; LH, luteinizing hormone.