Women in the United States who followed a Mediterranean-style diet – heavy on fresh foods, fish, and olive oil – around the time of conception had lower risk of developing a pregnancy complication, results of a large new study suggest.
The study included 7,798 women who had not given birth before. The group was geographically, racially, and ethnically diverse.
Researchers led by Nour Makarem, PhD, MS, with the department of epidemiology, Columbia University, New York, published their results in JAMA Network Open.
“Generally, higher intakes of vegetables, fruits, legumes, fish, and whole grains and lower intakes of red and processed meat were associated with lower risk of APOs [adverse pregnancy outcomes],” the authors wrote.
21% lower risk of complications
The investigators found that women in the study – who were part of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be, which enrolled 10,038 women between Oct. 1, 2010, and Sept. 30, 2013, and scored high on adherence to a Mediterranean diet – had a 21% lower risk of developing any adverse pregnancy outcome (APO) than those who had low adherence. And the better the adherence, the lower the risk of adverse outcomes, especially preeclampsia or eclampsia and gestational diabetes, the researchers wrote.
The research team also studied how following the diet correlated with gestational high blood pressure, preterm birth, delivery of a small-for-gestational-age infant, and stillbirth.
Women were scored on consumption of nine components: vegetables (excluding potatoes), fruits, nuts, whole grains, legumes, fish, monounsaturated to saturated fat ratio, red and processed meats, and alcohol.
No differences by race, ethnicity, or BMI
There were no differences in adverse pregnancy outcomes by race, ethnicity, or the woman’s body mass index before pregnancy, but associations were stronger in the women who were 35 years or older, according to the paper.
The authors pointed out that the women in the study had access to prenatal care at a large academic medical center during their first 3 months of pregnancy so the study may actually underestimate the importance of the diet in the pregnancy outcomes.
Christina Han, MD, division director of maternal-fetal medicine at University of California, Los Angeles, who was not part of the study, said that the results make sense as the researchers looked at the time of conception, which is a time that reflects the way a person chooses to live their life.
“We know that your health state as you enter pregnancy can significantly affect your outcomes for that pregnancy,” she said. “We’ve known for decades now that a Mediterranean diet is good for just about everybody.”
Unequal access to foods on diet
Dr. Han said that, while it’s great the researchers were able to confirm the benefit of the Mediterranean diet, it highlights inequity as lower income people are not as likely to be able to afford fresh fruits and vegetables and fish.
“This is a call to arms for our food distribution system to even out the big divide in what patients have access to,” Dr. Han said.
She noted that most of the women in this study were married, non-Hispanic White, and had higher levels of education which may make it hard to generalize these results to the general population.
A limitation of the study is that the women were asked to report what they ate themselves, which can be less accurate than when researchers record what is eaten in a controlled setting.
The researchers suggested a next step: “Long-term intervention studies are needed to assess whether promoting a Mediterranean-style diet around the time of conception and throughout pregnancy can prevent APOs.”
Dr. Makarem reported receiving grants from the National Institutes of Health and the American Heart Association outside the submitted work. One coauthor reported receiving grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development during the study. One coauthor reported receiving personal fees for serving on the board of directors for iRhythm and from fees paid through Cedars-Sinai Medical Center from Abbott Diagnostics and Sanofi outside the submitted work, and one coauthor reported serving as a clinical end point committee member for GlaxoSmithKline outside the submitted work. No other disclosures were reported. Dr. Han reported no relevant financial relationships.