Table 1.

Age-standardized baseline characteristicsa of 47,555 participants in the Black Women's Health Study

Oral contraceptive use
EverNever
Age, mean (SD)36.6 (116.5)39.2 (170.8)
Education, %
 <High school1.84.3
 High school13.517.0
 College24.422.8
 Graduate21.921.4
Marital status, %
 Single37.248.7
 Married/living together39.129.3
 Separated/divorced/widowed22.820.9
Age at menarche12.3 (20.8)12.3 (22.0)
History of infertility, %10.09.8
Parous, %63.450.3
Postmenopausal, %8.222.0
BMI (kg/m2)29.0 (93.1)30.5 (109.8)
Vigorous physical activity, hours/week, %
 1–453.047.5
 ≥513.312.2
Ever use of estrogen-only FMH, %b2.63.4
Ever use of estrogen+progestin FMH, %b8.79.0
Ever use of progestin-only female hormones, %b1.61.1
  • aValues are means (SD) or percentages and are standardized to the age distribution of the study population.

  • bAmong women age ≥40 years and not taking oral contraceptives.