Effect of dietary and lifestyle intervention in pregnant women: randomized clinical trial

OBJECTIVE: To evaluate the intra- and between-group (control and intervention) effect of counseling during pregnancy on pregnant women’s food consumption and physical activity. METHODS: This randomized, parallel, two-arm clinical trial was carried out in primary health care in a Brazilian municipality from 2018 to 2021. Adult pregnant women with pre-gestational overweight (n = 350) were randomly assigned to the control or intervention groups. The intervention consisted of three counseling sessions based on the NOVA food classification system and encouragement toward physical activity. Then, 24-hour dietary records were obtained, and physical activity was assessed using a structured questionnaire. The Wilcoxon test was used for intra-group differences between assessments and the Mann-Whitney test, for differences between groups. RESULTS: Women in the control group consumed less minimally and unprocessed foods (%E) (Δ = −4.08; -13.58 to 4.34; p = 0.006) and more ultra-processed foods (%E) (Δ = 3.74; −5.86 to 12.86; p = 0.009), with no difference between groups. The intervention group showed an increase in commuting-related physical activity (min/week) between assessments (Δ = 9.00; −30.00 to 70.00; p = 0.02), with no difference between groups. The other parameters showed no differences. CONCLUSIONS: The intervention failed to affect outcomes. However, intragroup changes showed that the control consumed less minimally and unprocessed foods and more ultra-processed foods and the intervention group increased their commuting-related physical activities.