Fertility outcomes in women with pre-existing type 2 diabetes—a prospective cohort study

Objective: To study childbirth and the risk of miscarriage and infertility among women who have received a diagnosis of type 2 diabetes before the start of their reproductive journey. Design: Register-based cohort study using the Skåne Healthcare Register Setting: All healthcare visits for the whole population of the southernmost region in Sweden over the past 20 years Patient(s): All women who were aged 18–45 years between January 1, 1998 and December 31, 2019 and who received a clinical diagnosis of type 2 diabetes before their first childbirth, miscarriage, or infertility diagnosis (n = 230) were compared with a healthcare-seeking population of women without any type of diabetes, matched for calendar year and age (n = 179,434). Intervention(s): None Main Outcome Measure(s): Childbirth, miscarriage, and infertility diagnosis Result(s): The birthrate was lower among women with type 2 diabetes (62.6% vs. 83.8%), and they were less likely to give birth (crude risk ratio [RR] = 0.73, 95% confidence interval [CI]: 0.66–0.81). They had a higher risk of experiencing a miscarriage (RR = 1.88, 95% CI: 1.50–2.36). The risk of infertility was increased (RR = 3.44, 95% CI: 2.88–4.10) as was the risk of having infertility and not giving birth (RR = 4.47, 95% CI: 3.44–5.82). All results remained the same after adjustment for polycystic ovary syndrome and obesity. Conclusion(s): Women with type 2 diabetes with onset before their reproductive journey were more often childless compared with women without diabetes and had a higher risk of experiencing both miscarriage and infertility. This patient group may be in need of targeted information regarding potential fertility issues as part of their clinical treatment.