The study, published in The American Journal of Clinical Nutrition, was led by professionals from BCNatal (Hospital Clínic and Hospital Sant Joan de Déu), IDIBAPS, and the Sant Joan de Déu Research Institute (IRSJD).
Increased consumption of ultra-processed foods between the second and third trimesters significantly raises the risk of preeclampsia
The study analyzes data from 812 pregnant women participating in the IMPACT BCN clinical trial, which includes more than 1,200 pregnancies at high risk of having babies small for gestational age. Researchers assessed changes in the ultra-processed foods consumption between the second and third trimesters of pregnancy using detailed dietary questionnaires.
In the study population, the consumption of ultra-processed foods represents approximately 17% of total caloric intake, with sugary drinks, sweets, and pastries being the main contributors during pregnancy.
The results show that women who increased their consumption of these foods during this period had more than twice the risk of developing preeclampsia compared to those who reduced their consumption.
Preeclampsia, which affects between 2% and 6% of pregnancies, is characterized by high blood pressure and damage to maternal organs after the 20th week of pregnancy and can have serious consequences for both mother and baby.
Alejandra Trejo-Domínguez, a researcher at BCNatal and first author of the study, comments: "Our results suggest that increased consumption of ultra-processed foods during pregnancy could have an impact on the risk of developing preeclampsia." Francesca Crovetto, senior author of the study, adds: "Although further research is needed to confirm this relationship, our data reinforce the importance of promoting a diet based on fresh or minimally processed foods during pregnancy."
Furthermore, Sara Castro-Barquero, a dietitian-nutritionist and postdoctoral researcher at BCNatal, and senior author of the study, comments: “Ultra-processed foods—such as sugary drinks, processed snacks, processed meats, and pre-cooked meals—are commonly associated with diets of lower nutritional quality. In the study, participants with a higher consumption of these products also showed a higher intake of calories, saturated fats, and sugars, as well as a lower presence of fresh or minimally processed foods in their diets.”
Following a Mediterranean diet during pregnancy can reduce the risk of obstetric complications
According to the research team, these results reinforce the importance of diet during pregnancy as a potentially modifiable factor in reducing obstetric complications.
The study also shows that interventions that promote the Mediterranean diet during pregnancy can help reduce consumption of ultra-processed foods. Participants who followed this dietary intervention significantly decreased their intake of these products and increased their consumption of fresh foods.
According to the researchers, these results suggest that promoting healthy eating patterns during pregnancy, such as the Mediterranean diet, could be an effective strategy for improving maternal diet quality and reducing risk factors associated with pregnancy complications.
Furthermore, they point out that although the study was conducted in a population of high-risk pregnancies and further research is needed to confirm these results in other contexts, the findings provide new evidence on the role of diet and the consumption of ultra-processed foods in maternal health during pregnancy.
Study of reference:
Ultraprocessed foods consumption and risk of preeclampsia: a secondary analysis of the improving mothers for a better prenatal care trial Barcelona (IMPACT BCN) randomized clinical trial. Alejandra Trejo-Domínguez et al. The American Journal of Clinical Nutrition. 2026.
