Objective: To evaluate the nutritional risk of hospitalized pregnant women in a hospital of high complexity, using the nutritional screening tool in OLNUT pregnant women. Material and methods: Observational, transverse cohort study of 258 hospitalized pregnant women. Nutritional risk was assessed at admission to the hospital by means of a screening tool, which investigated four key aspects: Implications of clinical diagnosis in nutritional status, changes in diet, classification of pregestational and gestational BMI, which allowed the classification of the population Depending on nutritional risk and refer to a nutritional care plan. Results: High nutritional risk was detected in 194 patients (75.2%), with the screening tool. A total of 117 patients (45.3%) of the population were hospitalized with clinical diagnoses that impacted the nutritional status, and it was important to note that 158 (61.2%) pregnant women started the pregnancy with a normal BMI, and 121 (46.9%) had hospital admission. Of the pregnant women still maintained the BMI within parameters of normality. Conclusions: The nutritional screening tool in OLNUT pregnant women allows, in a simple way, to establish the nutritional risk of pregnant women on admission to the hospital.