A description of the methods of the aspirin supplementation for pregnancy indicated risk reduction in nulliparas (ASPIRIN) study.

BACKGROUND Preterm birth (PTB) remains the leading cause of neonatal mortality and long term disability throughout the world. Though complex in its origins, a growing body of evidence suggests that first trimester administration of low dose aspirin (LDA) may substantially reduce the rate of PTB. METHODS Hypothesis: LDA initiated in the first trimester reduces the risk of preterm birth. Study Design Type: Prospective randomized, placebo-controlled, double-blinded multi-national clinical trial conducted in seven low and middle income countries. Trial will be individually randomized with one-to-one ratio (intervention/control) Population: Nulliparous women between the ages of 14 and 40, with a singleton pregnancy between 6 0/7 weeks and 13 6/7 weeks gestational age (GA) confirmed by ultrasound prior to enrollment, no more than two previous first trimester pregnancy losses, and no contraindications to aspirin. INTERVENTION Daily administration of low dose (81 mg) aspirin, initiated between 6 0/7 weeks and 13 6/7 weeks GA and continued to 36 0/7 weeks GA, compared to an identical appearing placebo. Compliance and outcomes will be assessed biweekly. OUTCOMES Primary outcome: Incidence of PTB (birth prior to 37 0/7 weeks GA). Secondary outcomes Incidence of preeclampsia/eclampsia, small for gestational age and perinatal mortality. DISCUSSION This study is unique as it will examine the impact of LDA early in pregnancy in low-middle income countries with preterm birth as a primary outcome. The importance of developing low-cost, high impact interventions in low-middle income countries is magnified as they are often unable to bear the financial costs of treating illness. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT02409680 Date: March 30, 2015.