Table 1—

Descriptive characteristics of women with and without type 1 diabetes

Type 1 diabetesWithout diabetes
P
SistersControl subjects
n143186158
Mean age at exam (years)42.6 ± 5.442.4 ± 8.341.2 ± 6.40.22
Age at menarche (years)13.5 ± 1.912.5 ± 1.412.6 ± 1.4<0.001
Ever oral contraceptive use (%)44.079.079.8<0.001
Ever pregnant (%)76.883.970.30.01
Mean number of pregnancies*2.3 ± 1.62.9 ± 1.42.6 ± 1.4<0.001
Infertility (%)16.917.716.60.96
Miscarriages (%)*31.232.127.90.76
Stillbirths (%)*10.10.60.9<0.001
Natural menopause (%)12.512.79.80.69
Mean age at natural menopause (years)41.6 ± 10.649.9 ± 6.147.8 ± 4.60.06
Ever smoked (%)41.848.450.00.33
College attendance (%)64.665.675.90.06
Income ≥$40,000 (%)40.859.152.70.006
Mean BMI (kg/m2)24.6 ± 4.525.2 ± 5.327.4 ± 7.30.003
Hashimoto’s thyroiditis (%)42.730.419.6<0.001
Age Hashimoto’s detected (years)38.1 ± 9.342.0 ± 10.239.2 ± 9.70.14
  • Data are mean ± SD.

  • *

    * These analyses excluded women that had never been pregnant;

  • these analyses excluded women with a premenopausal hysterectomy or bilateral oophorectomy and were based on 120, 165, and 143 women, respectively, of whom 15, 21, and 14 experienced natural menopause.