Omega-3 supplementation may cut risk of premature delivery in certain expectant mums

Women with low levels of omega-3 in early pregnancy may lower their risk of early preterm birth by taking supplements, as suggested in a study.

For the study, researchers conducted an exploratory analyses of a multicentre, double-blind trial that included 5,328 singleton pregnancies in 5,305 women recruited before 20 weeks of gestation. These women were randomly assigned to receive fish oil capsules containing 900-mg omega-3 long-chain polyunsaturated fatty acids (n=2,654) or vegetable oil capsules (n=2,674). Supplementation was given daily, from enrolment until 34 weeks of gestation.

Of the pregnancies, 91 (1.7 percent) resulted in early preterm birth (<34 weeks’ gestation) while 378 (7.1 percent) resulted in preterm birth (<37 weeks’ gestation). The median maternal age at baseline was 30.0 years, and the median gestational age was 14.1 weeks for the overall cohort.

Logistic regression models showed that omega-3 supplementation did little to reduce the likelihood of early preterm birth in the overall cohort (1.81 percent vs 1.61 percent; odds ratio [OR], 1.13, 95 percent confidence interval [CI], 0.74–1.71).

However, supplementation reduced the odds of early preterm birth by 70 percent in the subgroup of women with low total omega-3 status in early pregnancy (OR, 0.30, 95 percent CI, 0.10–0.93). No additional maternal characteristics modified the effect of omega-3 supplementation on this outcome.

For preterm birth, on the other hand, omega-3 supplementation was beneficial to women who were multiparous (OR, 0.65, 95 percent CI, 0.49–0.87) and those who avoided alcohol in the lead up to pregnancy (OR, 0.62, 95 percent CI, 0.45–0.86).