Analysis criteria: The prevalences of asthma (or asthma-like symptoms) and AHR will be of 30% and 50% (based on a personal preliminary study), respectively. The FDI and CVTV will be compared in obese women with and without AHR and in healthy women (primary objective), and subsequently in obese asthmatic women and obese non asthmatic women. The measurement of exhaled NO and the bronchomotor effect of deep inhalation will allow the determination of underlying pathophysiology of obesity-related asthma (secondary objective).