Study highlights racial differences for DHA intakes, calls for optimizing DHA status in pregnancy

30-Apr-2024 - Last updated on 30-Apr-2024 at 15:10 GMT

Black women have, on average, lower DHA omega-3 levels and higher risk of preterm birth, but high dose supplementation with DHA may reduce the risk of preterm birth and early preterm birth, says a new study.

Previous reports show the importance of DHA levels for reducing the risk of preterm birth, but it was now previously known if there were racial differences in DHA efficacy during pregnancies.

Researchers from the University of Kentucky, the University of Arizona and the University of Kansas Medical Center now report that analysis of data from a randomized controlled adaptive design multicenter trial showed that high dose supplementation (1,000 mg/d of DHA) led to significant reductions in preterm birth (PTB) for all women, regardless of race, but only Black women also had reductions in early preterm birth (EPTB), defined as birth prior to 34 weeks of gestation.

“High baseline DHA levels and supplementation with high-dose DHA in pregnancy reduce the racial disparity in PTB rates, despite more risk factors for PTB among Black pregnant individuals,” wrote the researchers in the American Journal of Obstetrics & Gynecology MFM.

“Our data demonstrate the importance of optimizing the DHA status of reproductive-aged women and supplementation with higher doses of DHA in pregnancy to mitigate the racial disparity in PTB outcomes.”

Study details

The new study relied on data from 1,032 pregnant women who were randomly assigned to receive either 200 mg per day of DHA (the low dose group) or 1,000 mg per day of DHA (the high dose group) from approximately 20 weeks of gestation to the birth of their child. Of the 1,032 women in the study, 236 identified as non-Hispanic Black or African American women.

The researchers measured DHA status (as red blood cell phospholipid fatty acid DHA) when the women joined the study, and again at delivery, and compared this to pregnancy outcomes. Preterm birth was defined as delivery before 37 weeks, and early preterm birth was defined as delivery before 34 weeks.

The results showed that, at enrollment, DHA levels were lower among the Black women, compared to the non-Black women.

While the high-dose DHA group reduced preterm birth for all participants, and for early preterm birth only for the Black participants, the rate of preterm birth and early preterm birth were still higher among the Black participants compared to the non-Black participants.

Specifically, “the rate of PTB was more than 2-fold higher for Black participants than for non-Black at both DHA doses, whereas the rates of EPTB were 4.5-fold higher for the 200-mg dose and 2.9-fold higher for the 1,000-mg dose,” the researchers wrote.

In addition, women with the highest average DHA levels at the start of the study, (at least 6% RBC-PL-DHA) had a lower early preterm birth rate compared to those with lower DHA levels. This result was consistent for all races and both DHA doses.

A clear need for DHA supplementation

Commenting independently on the findings, Harry Rice, PhD, VP of regulatory and scientific affairs at the Global Organization for EPA and DHA Omega-3s (GOED), told us: “For Black women, Dr. Carlson and her colleagues report a clear need for increasing DHA status in advance of pregnancy as well as supplementing with enough DHA during pregnancy, in order to reduce the risk of preterm birth. With the evidence in hand, the challenge is going to be translating the findings into practice.

“Undoubtedly, this is the kind of data that needs to be considered by a dietary reference intake (DRI) review committee when evaluating the evidence to set a DRI for EPA and DHA at different life stages.”

Economic benefits

The study adds to an ever-growing body of science supporting the potential benefits of DHA supplementation during pregnancy for mother and baby.

The reduction in the risk of pre-term birth also offers significant economic benefits. For example, analysis of data from the Kansas University DHA Outcomes Study (KUDOS) found that this would result in cost savings of $1,678 per infant. Taking out the $166.48 cost of the DHA supplements for 26 weeks and a $26 increase in maternal care costs, the net saving became $1,484.

For the nearly four million live births in the U.S. every year, this cost saving would become almost $6 million, according to data published in 2016 in Prostaglandins, Leukotrienes and Essential Fatty Acids (Vol. 111, pp. 8–10).

Source: American Journal of Obstetrics & Gynecology MFM
May 2024, Volume 6, Issue 5, 101358, doi: 10.1016/j.ajogmf.2024.101358
“Racial disparity in efficacy of docosahexaenoic acid supplementation for prevention of preterm birth: secondary analysis from a randomized, double-blind trial”
Authors: E.A. DeFranco et al.