Table 1

Characteristics of study participants among women with a history of gestational diabetes in the NHSII and the DNBC

CharacteristicsNHSII (n=1884)DNBC (n=550)
Type 2 diabetes cases, n (%)446 (23.7)155 (28.2)
Length of follow-up (years), mean±SD21.3±5.612.7±1.5
Age at the index pregnancy (years), mean±SD30.5±5.331.7±4.6
Age at the last follow-up* (years), mean±SD56.0±6.343.8±4.7
Family history of diabetes at the index pregnancy†, n (%)472 (28.6)204 (37.1)
Pre-pregnancy smoking, n (%)55 (8.4%)145 (26.4)
Pre-pregnancy BMI, n (%)
 <25 kg/m2335 (51.2)209 (38.0)
 25–29 kg/m2171 (26.2)149 (27.1)
 ≥30 kg/m2148 (22.6)150 (27.3)
  • *In the NHSII, the last follow-up was the date of last questionnaire return, date of death or date of type 2 diabetes cases, whichever occurred earliest; in DNBC, the last follow-up was the follow-up clinical exam.

  • †In the NHSII, for women who reported GDM before 1989, it refers to characteristics at 1989.

  • BMI, body mass index; DNBC, Danish National Birth Cohort; NHSII, Nurses’ Health Study II.