Associations between aspirin prophylaxis and fetal growth and preeclampsia in women with pregestational diabetes

Background: Current guidelines recommend low-dose aspirin for preeclampsia prophylaxis in all women with pregestational (type one and type two) diabetes mellitus. Most trials showing the efficacy of low-dose aspirin in reducing preeclampsia risk have either excluded or included only small numbers of such women. Aim: To evaluate the association of low-dose aspirin prophylaxis in women with pregestational diabetes with the incidence of large for gestational age (LGA) infants and preeclampsia. Materials and Methods: A retrospective observational study of pregnancies to women with pregestational diabetes. Outcomes included rates of LGA and preeclampsia. Women were prescribed low-dose aspirin prophylaxis from early pregnancy according to physician discretion after considering preeclampsia risk. Statistical analyses assessed the group overall and with stratification by diabetes type and other preeclampsia risk factors. Results: Of 716 pregnancies, aspirin was prescribed in 296 (41%). Preeclampsia occurred more frequently in women who received aspirin (58 of 296, 20%) than those who did not (39 of 420, 9%, P < 0.001). This association was maintained after adjustment for diabetes type and other preeclampsia risk factors (adjusted odds ratio (aOR) 1.78; 95% CI 1.02–3.11). LGA infants were commoner in women with type one diabetes of short duration who took aspirin (aOR 2.21; 95% CI 1.05–4.66). Conclusion: Low-dose aspirin use in women with pregestational diabetes may be associated with an increased risk of preeclampsia. In women with type one diabetes of short duration aspirin use may be associated with an increased risk of LGA infants. The retrospective nature of this study is acknowledged and assessment of such prophylaxis by further studies is warranted.