Article History
Received: 25 August 2021
Accepted: 23 February 2022
First Online: 2 March 2022
Declarations
:
: The study protocol was approved by the institutional review board of the hospital region (Helsinki and Uusimaa Hospital District Committee for Obstetrics and Gynecology, HUS/3172/2018 and HUS/54/2019). Due to the retrospective nature of the study, written informed consent was waived according to national legislation (Medical Research Act 488/1999, chapter 2 a (23.4.2004/295), section 5 and 10a). The study was performed with the relevant guidelines and regulations and in accordance with the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.