ABSTRACT
OBJECTIVE: To assess the number and sex ratio of children in individuals with Type 1 diabetes mellitus and the influence of parental diabetes on age at onset of Type 1 diabetes in our cohort. METHODS: In a cross-sectional study in a German region comprising 350,000 inhabitants, 697 subjects with Type 1 diabetes (364 women, 333 men) underwent a standardized assessment regarding the number and sex of their children and the family history of diabetes. RESULTS: Compared with 1.36 children per woman in the German background population, the total fertility rate in the calendar year of 2010 in our female cohort with Type 1 diabetes (age 18-49 years) was 0.88. Men with Type 1 diabetes had a fertility rate of 0.65. More men (51.1%) than women (35.7%; P < 0.0001) were childless. Twenty per cent of all women aged 41-45 years in the background population were childless compared with 36.2% of all women and 52% of all men in this specific age group from our cohort. The sex ratio of female vs. male offspring of individuals with Type 1 diabetes did not differ significantly from the expected 1:1 ratio. Maternal Type 1 or Type 2 diabetes increased the age at onset of Type 1 diabetes from 22.9 ± 13.7 (no maternal diabetes) to 28.6 ± 16.8 and 30.1 ± 15.1 years (p < 0.0001), respectively. CONCLUSIONS: Compared with the German reference population, individuals with Type 1 diabetes had significantly fewer children and were more often childless. The sex ratio female vs. male offspring of women and men with Type 1 diabetes was unaffected. Maternal history of Type 1 and Type 2 diabetes was associated with a significant later onset of Type 1 diabetes.
