Taking omega-3 long-chain polyunsaturated fatty acids during pregnancy was associated with reduced risk of preterm birth, and also may reduce the risk of babies born at a low birth weight and risk of requiring neonatal intensive care, according to a Cochrane review of 70 randomized controlled trials.
Creatas Images
“There are not many options for preventing premature birth, so these new findings are very important for pregnant women, babies, and the health professionals who care for them,” Philippa Middleton, MPH, PhD, of Cochrane Pregnancy and Childbirth Group and the South Australian Health and Medical Research Institute, in Adelaide, stated in a press release. “We don’t yet fully understand the causes of premature labor, so predicting and preventing early birth has always been a challenge. This is one of the reasons omega-3 supplementation in pregnancy is of such great interest to researchers around the world.”
Dr. Middleton and her colleagues performed a search of the Cochrane Pregnancy and Childbirth’s Trials Register, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform and identified 70 randomized controlled trials (RCTs) where 19,927 women at varying levels of risk for preterm birth received omega-3 long-chain polyunsaturated fatty acids (LCPUFA), placebo, or no omega-3.
“Many pregnant women in the UK are already taking omega-3 supplements by personal choice rather than as a result of advice from health professionals,” Dr. Middleton said in the release. “It’s worth noting though that many supplements currently on the market don’t contain the optimal dose or type of omega-3 for preventing premature birth. Our review found the optimum dose was a daily supplement containing between 500 and 1,000 milligrams of long-chain omega-3 fats (containing at least 500 mg of DHA [docosahexaenoic acid]) starting at 12 weeks of pregnancy.”
In 26 RCTs (10,304 women), the risk of preterm birth under 37 weeks was 11% lower for women who took omega-3 LCPUFA compared with women who did not take omega-3 (relative risk, 0.89; 95% confidence interval, 0.81-0.97), while the risk for preterm birth under 34 weeks in 9 RCTs (5,204 women) was 42% lower for women compared with women who did not take omega-3 (RR, 0.58; 95% CI, 0.44-0.77).
With regard to infant health, use of omega-3 LCPUFA during pregnancy was associated in 10 RCTs (7,416 women) with a potential reduced risk of perinatal mortality (RR, 0.75; 95% CI, 0.54-1.03) and, in 9 RCTs (6,920 women), a reduced risk of neonatal intensive care admission (RR, 0.92; 95% CI, 0.83-1.03). The researchers noted that omega-3 use in 15 trials (8,449 women) was potentially associated with a reduced number of babies with low birth weight (RR, 0.90; 95% CI, 0.82-0.99), but an increase in babies who were large for their gestational age in 3,722 women from 6 RCTs (RR, 1.15; 95% CI, 0.97-1.36). There was no significant difference among groups with regard to babies who were born small for their gestational age or in uterine growth restriction, they said.
While maternal outcomes were examined, Dr. Middleton and her colleagues found no significant differences between groups in factors such as postterm induction, serious adverse events, admission to intensive care, and postnatal depression.
“Ultimately, we hope this review will make a real contribution to the evidence base we need to reduce premature births, which continue to be one of the most pressing and intractable maternal and child health problems in every country around the world,” Dr. Middleton said.
The National Institutes of Health funded the review. The authors reported no conflicts of interest.
SOURCE: Middleton P et al. Cochrane Database Syst Rev. 2018; doi: 10.1002/14651858.CD003402.pub3.