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 <37 weeks (23% vs. 27%, p=0.30), preterm delivery with preeclampsia (7% vs. 7%, p=0.96), and large and small for gestational age infants (40% vs. 32% (p=0.07) and 7% vs. 6% (p=0.88), respectively) were similar in the two cohorts.

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.


N. C. Do: None. M. Vestgaard: None. B. Ásbjörnsdóttir: 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.

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