Use of oral contraceptives in three European countries: a population-based multi-database study.

Objectives: The aim of the study was to assess the prevalence of oral contraceptive (OC) use, user characteristics and prescribing patterns by accessing health care databases of three European countries.
Methods: A retrospective study was performed from 2009 to 2010 in three general practice (GP) databases from the Netherlands, UK and Italy and in one database of linked pharmacy and hospitalisation data in the Netherlands. The presence of selected chronic conditions and diagnoses of diseases associated with OC use were assessed, as were switches, discontinuations and types of OC used during the study period.
Results: Among 2.16 million women aged 15 to 49 years, 16.0% were using an OC on 1 January 2010. The prevalence ranged from 19.7% in a Dutch database to 2.6% in the Italian database. During 2009 and 2010, mainly second-generation progestogens were prescribed in the Netherlands (79.4% and 78.3% of users), both second- (57.9%) and third-generation progestogens (43.6%) were prescribed in the UK, and mainly third-generation progestogens in Italy (61.8%). Most switches were to third- or fourth-generation pills. The prevalence of chronic diseases tended to be higher among OC users, and the proportions of women with a history of disease associated with OC use tended to be lower than among non-users.
Conclusions: Second-generation OCs were most frequently prescribed in the Netherlands. In the UK, and even more so in Italy, many women used third- or fourth-generation OCs. Preparation switches were mainly to third- or fourth-generation OCs. Among OC users, a somewhat higher prevalence of chronic diseases was observed; however, information bias cannot be ruled out.