Eating a high-quality diet during late pregnancy reduced the risk of fetal growth restriction, according to a new study presented at the Society for Maternal-Fetal Medicine virtual meeting held earlier this month.¹

Wang et al conducted a secondary analysis of data from a prospective cohort study in patients with singleton pregnancies who completed the NIH Dietary Health Questionnaire II (DHQ-II) in the third trimester or within 3 months of delivery. They did not include IVF pregnancies or patients with fetal anomalies and those who delivered at an outside hospital. The objective was to find the association between a high-quality diet during pregnancy and fetal growth restriction (FGR) (defined as fetal weight less than 10th percentile at birth) using the Healthy Eating Index (HEI). A score of ≥70 was taken to be indicative of a high-quality diet, while score <70 was considered as a low-quality diet.

A total of 762 patients answered the questionnaire. Results showed that out of the 762 participants, a mere 17% (n = 128) had a high HEI score, while 83% (n = 634) (83%) had low scores; the mean HEI score was 60.

After adjusting for obesity and chronic hypertension, pregnant women with a high HEI were 67% less likely to have FGR (adjusted rate ratio 0.33). About 4.7% of participants with a high quality diet had FGR, while nearly 14% of women with a low quality diet had FGR. The risk of hypertensive disorders of pregnancy was also 54% lower (aRR 0.46) with a high-quality diet. While 8.6% of women with a high quality diet developed hypertensive disorder, this increased to nearly 22% among women with a low quality diet.

No significant association of diet quality with large-for-gestational age, preterm birth, gestational diabetes, or unplanned cesarean delivery was found.

This research has highlighted the usefulness of the Healthy Eating Index as a tool to assess the quality of diet and nutritional status of women during pregnancy. A high-quality diet was found to positively influence fetal growth. Most of the participants had a low diet quality, which the authors speculate could have been due to socioeconomic factors influencing accessibility of affordable foods of high nutritional value. Assessing diet quality during pregnancy provides physicians an opportunity for interventions to improve their modifiable dietary risks to prevent pregnancy complications, it also empowers patients to take control of their diet for better maternal and fetal health.

Reference

1. Wang XY, et al. Diet quality in pregnancy and the risk of fetal growth restriction. Am J Obstet Gynecol. 2022 Jan. 1;226(1 Suppl): S21-S22 DOI: https://doi.org/10.1016/j.ajog.2021.11.081