A study published in August 2023 in the American Journal of Obstetrics and Gynecology has shown the benefits of a plant-based diet in minimising the risk of developing hypertensive disorders during pregnancy. Abnormally high blood pressure during pregnancy carries risks to both mother and child, but this study suggests that following a vegan diet before and during pregnancy reduces such a risk.

The study, titled, “Prepregnancy plant-based diets and risk of hypertensive disorders of pregnancy”, was authored by  Makiko Mitsunami, Siwen Wang, Diana C. Soria-Contreras, Irene Souter, Janet W. Rich-Edwards,  and Jorge E. Chavarro from the Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, US.

The researchers followed nearly 11,500 adult women throughout the entirety of their reproductive years. The participants’ diets were evaluated using a validated food questionnaire about the frequency and quality of plant-based foods they consumed. This questionnaire was reassessed every four years to ensure accuracy as the participants’ lifestyles evolved. Using the results of the questionnaires, each participant was assigned a plant-based diet index (PDI), and those who best adhered to a plant-based diet were designated a higher score.

The researchers found that as the amount of animal products decreased and plant-based alternatives increased, the risk of women experiencing hypertensive disorders of pregnancy notably decreased. Women with the highest PDI ratings were reported to have had a 24% lower risk of hypertensive disorders of pregnancy than those with significantly lower PDI ratings. 

Dr Jorge E. Chavarro, one of the authors of the study, said, “We wanted to know how one’s diet leading up to pregnancy influences the pregnancy, so we monitored women for virtually their entire reproductive life, almost 20 years, and gained an awareness of their typical diet before pregnancy”. Talking about how reducing animal products appeared to be beneficial, he said, “It was clearer for pregnancy-related hypertension than for preeclampsia, but a diet made up primarily of plant-based foods seemed to be protective for both.”

“Originally from Catalonia, but resident in the UK for several decades, Jordi is a vegan zoologist and author, who has been involved in different aspects of animal protection for many years. In addition to scientific research, he has worked mostly as an undercover investigator, animal welfare consultant, and animal protection campaigner. He has been an ethical vegan since 2002, and in 2020 he secured the legal protection of all ethical vegans in Great Britain from discrimination in a landmark employment tribunal case that was discussed all over the world. He is also the author of the book, ‘Ethical Vegan: a personal and political journey to change the world’.