Longitudinal Randomized Controlled Study on the Effectiveness of Nutritional Education During Uncomplicated Pregnancy

The goal of this clinical trial is to evaluate whether a structured nutritional education intervention can improve gestational weight gain outcomes and related maternal and neonatal health indicators in women with uncomplicated pregnancy. The main question it aims to answer is whether a group-based nutritional education program increases the proportion of women achieving gestational weight gain within Institute of Medicine (IOM) recommended ranges compared with standard prenatal care. Researchers will compare a structured nutritional education intervention group to a control group receiving routine prenatal care and a nutritional information brochure to see if the intervention improves gestational weight gain within recommended ranges and affects maternal and neonatal outcomes. Participants in the intervention group will: * Attend three weekly group-based nutritional education sessions delivered by trained healthcare professionals * Attend one practical cooking (show-cooking) session Participants in the control group will: * Receive routine prenatal care and a written nutritional information brochure * Be followed from early pregnancy until 8 weeks postpartum All participants (including control group) will: * Record body weight regularly throughout pregnancy using a telemedicine system * Complete questionnaires on dietary intake and quality of life at multiple time points * Undergo assessments of body composition and urinary biomarkers of oxidative stress during pregnancy

This study is based on the hypothesis that dietary behavior during pregnancy plays a key role in determining maternal metabolic adaptation and pregnancy outcomes, particularly through its influence on gestational weight gain regulation and oxidative stress balance. Pregnancy is characterized by physiological metabolic and endocrine adaptations that increase susceptibility to both under- and over-nutrition. Inadequate dietary patterns may contribute to excessive gestational weight gain, which has been associated with increased risk of maternal and neonatal complications. Conversely, nutritional imbalance may also affect fetal development and long-term health trajectories. Despite existing recommendations for healthy eating during pregnancy, adherence in real-world settings remains suboptimal, suggesting the need for structured behavioral interventions. In addition to metabolic effects, pregnancy is associated with a physiological increase in oxidative stress, which is involved in placental development and fetal growth regulation. However, excessive oxidative stress has been linked to adverse outcomes including impaired placental function and increased risk of metabolic and hypertensive disorders. Dietary patterns rich in antioxidants, such as those emphasizing high-quality nutrients and balanced macronutrient intake, may contribute to modulating oxidative stress pathways. The intervention tested in this study is grounded in behavioral nutrition and health education principles, with the aim of improving dietary awareness, food selection skills, and long-term adherence to nutritional recommendations. The group-based format is designed to enhance engagement, facilitate peer interaction, and improve cost-effectiveness compared to individual counseling approaches. The study employs a randomized controlled design to minimize selection bias and allow causal inference regarding the effect of the intervention. Stratified randomization is used to ensure balance across clinically relevant prognostic factors, including pre-pregnancy BMI and parity, which are known to influence gestational weight gain and pregnancy outcomes. The longitudinal structure of the study allows evaluation of both short-term behavioral changes during pregnancy and medium-term maternal outcomes extending into the postpartum period. The integration of behavioral, anthropometric, and biochemical assessments enables a multidimensional evaluation of the intervention's impact.

Inclusion Criteria: * Pregnant women with gestational age ≤ 17 weeks at enrollment * Age ≥ 18 years * Ability to provide written informed consent * Availability of a personal smartphone for study participation and data reporting * Availability of a personal weight scale for home monitoring Exclusion Criteria: * Multiple pregnancy * Pre-existing hypertension * Pre-existing diabetes mellitus * Pre-pregnancy body mass index (BMI) \< 18.5 kg/m² * Pre-pregnancy body mass index (BMI) ≥ 35 kg/m² * History of psychiatric disorders * Overt hypothyroidism or hyperthyroidism * Celiac disease * Inflammatory bowel disease (ulcerative colitis or Crohn's disease) * History of bariatric surgery * Language barrier preventing comprehension of study procedures or completion of assessments