3: Randomized controlled trial of Omega-3 fatty acid supplementation for recurrent preterm birth prevention


      Omega-3 fatty acid (Ω3) supplementation and dietary intake have been reported to prolong gestation and decrease preterm birth (PTB). This trial was undertaken to evaluate whether Ω3 supplementation reduces recurrent PTB in women with prior PTB when given along with 17 alpha-hydroxyprogesterone caproate (17-OHPC). Dietary intake of fish was also evaluated.

      Study design

      In this randomized, double-masked, placebo controlled, multicenter trial, women with prior spontaneous (s)PTB and a singleton gestation were assigned to take either an Ω3 supplement (1200 mg eicosapentaenoic acid and 800 mg docosahexaenoic acid) or matching placebo (PL) daily from 16-22 through 37 wks’ gestation. All participants received weekly 17 OHPC (250mg) IM. A validated food frequency questionnaire was used to assess dietary intake of fish at baseline.


      Of the 852 women randomized, none were lost to follow up and all completed the food frequency questionnaire. (Table) The relative risk of PTB < 37 wks for Ω3 vs placebo was 0.91 (0.77-1.07), and when stratified by fish intake, 0.92 (0.78-1.08). However, women reporting ≥ 1 fish meal per month had significantly decreased PTB, odds ratio adjusted for baseline risk factors and treatment group: 0.62 (0.45- 0.86).
      Tabled 1
      Ω3PLp Ω3 vs PLFish ≥ 1 meal/monthFish < 1 meal/monthp Fish Intake
      PTB <37w37.8%41.6%0.2535.9%48.6%0.0005
      sPTB <37w29.0%31.8%0.3827.2%37.9%0.002
      PTB <35 w18.9%19.9%0.7217.2%24.5%0.014


      Among women with prior sPTB receiving 17-OHPC, omega-3 supplementation did not reduce the rate of PTB. We observed an association between dietary intake of fish and reduced PTB.