Text and Data Mining valid from 2019-05-20
Received: 29 April 2018
Accepted: 6 May 2019
First Online: 20 May 2019
Ethics approval and consent to participate
: The study protocol was approved by the institutional review board (IRB) of the Hospital District of Helsinki and Uusimaa (Helsinki and Uusimaa Hospital District Ethics Committee for Obstetrics and Gynecology, Pediatrics and Psychiatry). The permission was collectively granted for all three hospitals (Women’s Hospital, Maternity Hospital and Jorvi Hospital) included in the study. All three hospitals belong to Helsinki University hospital as well as to the hospital district of Helsinki and Uusimaa. According to national regulations (Medical Research Act 488/1999, chapter 2 a (23.4.2004/295), section 5 and 10a) and the IRB of the Hospital district of Helsinki and Uusimaa, no informed consent was required since this was a retrospective cohort study.
: Not applicable.
: The authors declare that they have no competing interests.
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