Aspirin Supplementation for Pregnancy Indicated Risk Reduction In Nulliparas (ASPIRIN): A Prospective randomized, placebo-controlled, double-blinded clinical trial in western Kenya.

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) holds promise to reduce the rate of PTB substantially.

Hypothesis:First trimester administration of aspirin will reduce the risk of preterm birth.

Study Design Type:Prospective randomized, placebo-controlled, double-blinded multicenter clinical trial. Trial will be individually randomized with one-to-one ratio (intervention/control)

Population:Nulliparous women between the ages of 18and 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. Minors who are ≥ 14 years of age may be enrolled if permitted by the country’s ethical guidelines. 

Intervention:Daily administration of low dose (81 mg) aspirin[also known as acetylsalicylic acid (ASA], 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: To determine whether daily LDA initiated between 6 0/7 -13 6/7 weeksGA and continued to 36 0/7 weeks GA reduces the risk of PTB (birth prior to 37 0/7 weeksGA).

Secondary outcomes of interest are the rate of preeclampsia/eclampsia, small for gestational age (SGA), and perinatal mortality.