Table 1.

Means (SD) and proportions of selected characteristics in the study population

Age, y30.7 (3.1)
Education, total years16.1 (3.0)
Ethnic minority, Sami, %7.8
Clinical measures
    Height, cm167.0 (6.5)
    Weight, kg68.1 (11.7)
    BMI, kg/m224.4 (3.8)
    Systolic blood pressure, mm Hg113 (11)
    Diastolic blood pressure, mm Hg71 (8)
    Heart rate, per min69 (11)
    Fasting serum glucose, mmol/L5.0 (0.6)
Menstrual and reproductive characteristics
    Age at menarche, y13.1 (1.4)
    Ever had a full-term pregnancy, %48.5
    Age at first full-term pregnancy, y24.5 (3.8)
    Cycle length, d28.3 (3.4)
    Salivary hormone concentration, pmol/L
        Overall average estradiol18.2 (9.4)
        Average midluteal estradiol19.9 (11.1)
        Overall average progesterone131.1 (68.7)
        Average midluteal progesterone163.4 (87.7)
Dietary intake
    Energy, kJ/d8,097 (1,891)
    Fat, g/d77.2 (23.7)
Physical activity, MET-hours/wk
    Occupational physical activity104 (79)
    Household activities80 (77)
    Recreational physical activity52 (36)
Alcohol consumption
    Teetotaller, %17.0
    Average use among alcohol consumers, units/wk3.5 (3.4)
    Ever smokers, %45.6
    Current smokers, %22.3
    Daily number of cigarettes among smokers10.1 (5.1)
Previous use of hormonal contraceptives
    Ever users, %80.6
    Total duration of use among ever users, y5.0 (3.5)
  • NOTE: The Norwegian EBBA study (n = 206). Number may vary due to missing information.

  • The conversion factor from mmol/L to mg/dL is 18 for serum glucose. The conversion factor from pmol/L to pg/mL is 0.272 for estradiol and 0.314 for progesterone.