Unchanged Prevalence of Preeclampsia After Implementation of Prophylactic Aspirin for All Pregnant Women With Preexisting Diabetes: A Prospective Cohort Study

OBJECTIVE: To evaluate the prevalence of preeclampsia after implementation of prophylactic aspirin for all pregnant women with preexisting diabetes compared with the prevalence in a previous risk-based prophylaxis.

RESEARCH DESIGN AND METHODS: A prospective observational cohort study of 410 consecutive pregnant women with preexisting diabetes categorized according to aspirin prophylaxis strategy, with the prevalence of preeclampsia as primary outcome. In total, 207 women were included after implementation of prophylactic aspirin for all pregnant women with preexisting diabetes in February 2018 (all-cohort). The 203 women included before this date, where aspirin prophylaxis was risk based and only prescribed to selected women (selected-cohort), were studied for comparison.

RESULTS: Aspirin was prescribed at ∼10 gestational weeks for 88% (all-cohort) compared with 25% (selected-cohort). HbA1c, parity, chronic hypertension, home blood pressure, microalbuminuria/diabetic nephropathy, and smoking were similar in the two cohorts in early pregnancy. In the all-cohort, fewer women had type 2 diabetes (32% vs. 42%, respectively; P = 0.04) and BMI tended to be lower (P = 0.05). The prevalence of preeclampsia was similar (12% vs. 11%, P = 0.69) in the two cohorts, and this was also the case with stratification for diabetes type. Prevalence of preterm delivery <37 weeks (23% vs. 27%, P = 0.30), preterm preeclampsia (7% vs. 7%, P = 0.96), and infants large (40% vs. 32%, P = 0.07) and small (7% vs. 6%, P = 0.88) for gestational age was similar in the two cohorts.

CONCLUSIONS: Implementation of prophylactic aspirin for all pregnant women with diabetes did not reduce the prevalence of preeclampsia compared with the previous risk-based prophylaxis in this cohort study.