2010 ; 7), et de larges études de cohorte en Europe (Oral contraceptive effectiveness according to body mass index, weight, age, and other factors, Dinger et al, Am J Obstet Gynecol, 2009; 201:263) et aux États-Unis (Effectiveness of oral contraceptive pills in a large US cohort comparing progestogen and regimen.
2010 ; 7), en belangrijke cohort studies in Europa (Oral contraceptive effectiveness according to body mass index, weight, age, and other factors, Dinger et al, Am J Obstet Gynecol, 2009; 201:263) en in de VS (Effectiveness of oral contraceptive pills in a large US cohort comparing progestogen and regimen.