Background: Pregestational type I and type II diabetes confer an unacceptably high perinatal mortality rate, up to tenfold the background population risk. This renders pregestational diabetes among the highest risk medical conditions in obstetrics. Pregestational diabetes represents a particularly high-risk for evolution of preeclampsia (PET), with incidence rates of PET within this group at approximately 20%. The combination of diabetes and preeclampsia places the pregnancy at heightened risk for hypoxia and stillbirth. The aetiology of PET remains unclear, although placental dysfunction, due to disordered early placental development, is central to the disease process. While not all adverse perinatal outcomes in women with pregestational diabetes are attributed to hypertensive disorders, any therapy that offers the potential to reduce the incidence of preeclampsia in this group deserves close attention. Low-dose aspirin has been investigated for the prevention of preeclampsia owing to its negative effect on thromboxane production. Studies investigating the role of aspirin in prevention of preeclampsia have varied in design, rarely investigate women with diabetes specifically, and generally initiate aspirin therapy too late in gestation to plausibly exert a benefit.
Study Objective: To investigate the effect of aspirin therapy initiated in the first trimester of pregnancy in women with pregestational type I or type 2 diabetes on a composite clinical measure of placental dysfunction (preeclampsia, preterm birth less than 34 weeks, birthweight below the 10th centile or perinatal mortality).
Study Design: A multicentre randomized double-blind placebo-controlled trial of daily low-dose aspirin 75mg initiated between 8+0 and 11+6 weeks gestational age until 36 weeks gestation, for women with a singleton pregnancy and a history of pre-pregnancy type I or type 2 diabetes of at least 6 months duration.
