Low fertility and the risk of type 2 diabetes in women

BACKGROUND: Fertility problems are frequently followed by early menopause, and early menopause has been associated with increased risk of type 2 diabetes (T2D). Thus far, it is unknown whether low fertility is independently associated with future T2D risk. METHODS: We assessed the association between measures of low fertility and T2D in the Prospect-European Prospective Investigation into Cancer and Nutrition (EPIC) cohort of 17 357 Dutch women, aged 49-70 years at baseline using Cox proportional hazards models, adjusted for various confounders. To investigate whether BMI and waist circumference influence the observed associations, analyses were additionally adjusted for these variables. RESULTS: At baseline, 332 women had T2D. During a mean follow-up of 9.1 +/- 3.6 years, 535 T2D cases occurred. Out of 15 707 Prospect-EPIC women who wanted to get pregnant, 1940 consulted a physician for fertility problems and 700 remained childless. No relation was found between consulting a physician for fertility problems or nulliparity and T2D risk. Of all women who wanted to get pregnant, 3946 (25.1%) had one or more miscarriages, with an average of 1.4 (+/- 0.9) miscarriages and a maximum of 10 miscarriages. Women who had one or more miscarriage showed the same risk for T2D as women who had no miscarriage. Also, none of the other measures of low fertility were associated with increased risk for T2D. CONCLUSIONS: Generally, measures of low fertility were not independently associated with a risk of T2D in a cohort of 17 357 Dutch women.