Department of Obstetrics and Gynecology, Hyvinkää Hospital, Hyvinkää, the Department of Obstetrics and Gynecology, Turku University Hospital, and the University of Turku, Turku, the Schools of Medicine and Health Sciences, University of Tampere, and the Department of Obstetrics and Gynecology, Tampere University Hospital, Tampere, and the Department of Obstetrics and Gynecology, Helsinki University Hospital, the University of Helsinki, and the Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki, Finland.
Corresponding author: Tuuli Soini, MD, Department of Obstetrics and Gynecology, Hyvinkää Hospital, Sairaalankatu 1, FI-05850 Hyvinkää, Finland; e-mail: [email protected].
Supported by research grants from Helsinki University Hospital and Hyvinkää Hospital.
The authors thank Docent Ritva Prättälä, National Institute for Health and Welfare, for her help in identifying the levonorgestrel-releasing intrauterine system users in the national health survey data and Miia Artama, PhD, from the University of Helsinki for her assistance with statistical analyses.
Financial Disclosure The authors did not report any potential conflicts of interest.
