Introduction: The St Vincent declaration stated that pregnancy outcomes in women with diabetes should approximate those of women without diabetes. We investigated in this study if this goal has been reached in Sweden.
Methods: Register based cohort study using the Swedish Medical Birth Register including data on all births 1998-2012 in Sweden. The time period was divided into 5 section comprising 3 years each, with 1998-2000 as the reference period. GDM was diagnosed using national criteria (75g oral glucose tolerance test, fasting glucose≥6.1 mmol/l and/or 2 hour glucose≥9 mmol/l: some regional differences), following screening if risk factors were present or a random glucose was >9 mmol/l. Logistic regression was performed to evaluate trends both for women with and without GDM. Women with pre-existing diabetes were excluded. Outcomes studied were pregnancy induced hypertension, preeclampsia, cesarean section, large for gestational age (LGA), small for gestational age (SGA), perinatal mortality, Erb’s palsy, birth trauma and hypoglycemia.
Results: We included 1,178,187 women in the study, of whom 14,833 were diagnosed with GDM (1%). There was no statistically significant difference in trends in outcomes for women with and without GDM. Rates of LGA and birth trauma decreased over the time period. In women with GDM, the rate of LGA decreased from 27.0% to 23.8%, OR per year 0.983(0.973-0.993). Birth trauma decreased from 2.0% to 0.9%, OR per year 0.926(0.894-0.959). Hypoglycemia in the offspring and SGA increased.
Conclusions: While some pregnancy outcomes have improved over time across all women, the gap between women with and without GDM remained relatively unchanged over 15 years. There was no difference in trend in outcomes for women with GDM and the background population. New ways are needed to improve GDM outcomes to achieve the St Vincents goals (eg earlier diagnosis, ‘tighter’ weight/glucose management)