Aspirin for Prevention of Preeclampsia

Comparison of Two Doses (81 mg Versus 162mg) of Aspirin for the Prevention of Preeclampsia in High-Risk Pregnant Women: A Randomized Controlled Trial

Prophylaxis with low-dose aspirin has been recommended to prevent preeclampsia, the rationale being that hypertension and abnormalities of coagulation in this disease are caused in part by an imbalance between vasodilating and vasoconstricting prostaglandins. Low-dose aspirin therapy inhibits thromboxane production more than prostacyclin production and therefore should protect against vasoconstriction and pathologic blood coagulation in the placenta. Initially, several single-center trials, mostly among women at increased risk for preeclampsia, demonstrated a substantial reduction in the risk of proteinuric hypertension as well as reductions in the incidences of preterm birth, infants small for gestational age, and perinatal death,

This will be a randomized control trial to estimate the efficacy of two doses (80 mg versus 160 mg) of aspirin for prevention of preeclampsia in High-Risk Pregnant Women identified in the first trimester to be at high risk.

This will be a randomized control trial to estimate the efficacy of two doses (80 mg versus 160 mg) of aspirin for prevention of preeclampsia in High-Risk Pregnant Women identified in the first trimester to be at high risk.

Aspirin 81mg two tablet once a day from recruitment until 37 weeks or labor whichever comes first plus placebo one tablet once a day from recruitment until 37 weeks or labor whichever comes first

The number of cases of preeclampsia that appear in both groups before 34 weeks of pregnancy.Blood pressure greater than 140/90 on 2 occasions 6 hrs apart and significant proteinuria (greater than 300 mg in 24 hrs) before 34 weeks gestation

The number of cases of fetal growth restriction, defined as a fetal weight below the 10th percentile and an abnormal umbilical cord doppler that appear in both groups at any given time during pregnancy.

The population of interest involves women attending the study hospital for antenatal care and delivery

Inclusion Criteria: Pregnant women presenting prior to 17+0 weeks' gestation. Moderate to high risk of preeclampsia. One or more of the following: previous history of preeclampsia, antiphospholipid antibodies, pre-existing diabetes, pre-existing hypertension, pre-existing renal disease, autoimmune disease, nulliparity, family history of preeclampsia, elevated BMI > 25, and maternal age <20 or >35. Give written informed consent. Exclusion Criteria: Multiple gestations, fetal aneuploidy major fetal structural anomaly bleeding disorder allergy to aspirin women already on aspirin or heparin.