Resumen: Objective: To determine the factors associated with sleep duration, daytime somnolence and insomnia before and after a period of classes and exams periods. Material and methods: 384 students (74.1% female) were evaluated, who reported their weight and height. The insomnia questionnaire and Epworth sleepiness scale were administered to each student during class period and exams period. Results: When comparing daytime somnolence, insomnia, sleep latency and the amount of sleeping hours between classes and exam periods an increase in sleep latency (p <0.05) was observed during exams. Fewer hours of sleep were observed in both periods (p <0.05) in women with overweight/obesity. In men, those who are overweight/obese show a higher daytime somnolence during exam periods (p <0.01). By performing the logistic regression analysis using daytime somnolence as a dependent variable, being a woman increases the risk of daytime somnolence (OR = 3.1, 95% CI 1.1 to 8.8), whereas the absence of insomnia is a protective factor for daytime somnolence (OR = 0.06, 95% CI 0.01 to 0.35). Conclusion: sleep latency is significantly increased during exam period, especially in women; in men a decrease is observed in sleep hours. Finally, women present high risk of diurnal somnolence, in difference the absence of insomnia is a protective factor, however the nutritional status and caffeine intake was not associated with sleeping problems.