946-P: Unchanged Prevalence of Preeclampsia after Implementation of Prophylactic Aspirin to All Pregnant Women with Preexisting Diabetes: A Prospective Cohort Study

Aim: To evaluate the prevalence of preeclampsia before and after implementing a change from a risk-based aspirin prophylaxis to prophylactic aspirin to all pregnant women with pre-existing diabetes. Methods: A prospective cohort study of 410 consecutive pregnant women with pre-existing diabetes (257 with type 1 and 153 with type 2 diabetes); 203 women (selected-cohort) prior to February 2018 where aspirin was prescribed to selected women at risk of preeclampsia followed by 207 women (all-cohort) who all were prescribed aspirin according to the new aspirin prophylaxis strategy. The primary outcome was preeclampsia. Results: Documented prescription of aspirin at approximately 10 weeks increased from 25% (selected-cohort) to 88% (all-cohort). In the all-cohort vs. selected-cohort HbA1c (median 46 mmol/mol (interquartile range 42-53) vs. 47 (43-53), p=0.18), parity, chronic hypertension, home blood pressure, microalbuminuria/diabetic nephropathy and smoking were similar in early pregnancy. In the all-cohort fewer women had type 2 diabetes (32% vs. 42%, p=0.04) and BMI tended to be lower (p=0.05). The prevalence of preeclampsia was unchanged (12% vs.11%, p=0.69) in the all- vs. selected-cohort and similar results were seen when stratifying for diabetes type. Preterm delivery Conclusion: Implementation of prophylactic aspirin to all pregnant women with pre-existing diabetes was not followed by a decline in the prevalence of preeclampsia. The possible effect of aspirin prophylaxis in women with diabetes needs to be further evaluated in randomized controlled trials. Disclosure N. C. Do: None. M. Vestgaard: None. B. Asbjornsdottir: Employee; Self; Novo Nordisk A/S. S. K. Noergaard: Research Support; Self; Novo Nordisk. L. Ringholm: Research Support; Self; Novo Nordisk. L. Andersen: None. D. M. Jensen: None. P. Damm: Advisory Panel; Self; Novo Nordisk A/S, Other Relationship; Self; Novo Nordisk A/S. E. R. Mathiesen: Advisory Panel; Self; Novo Nordisk, Research Support; Self; Novo Nordisk, Speaker’s Bureau; Self; Novo Nordisk, Sanofi-Aventis.