Funding for this research was provided by:
Svenska Forskningsrådet Formas
Östergötland County Council
Magnus Bergvalls Stiftelse
Fredrik och Ingrid Thurings Stiftelse
The Swedish Society of Medicine
Received: 14 February 2018
Accepted: 4 June 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: This study was conducted according to the Declaration of Helsinki and was approved by the central ethics board, Stockholm, Sweden (May 30, 2007; Dnr Ö 13–2007). Informed consent, witnessed and formally recorded, was obtained from all women.
: The authors declare they have no competing interests.
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