Text and Data Mining valid from 2019-07-11
Received: 16 February 2019
Accepted: 2 July 2019
First Online: 11 July 2019
Ethics approval and consent to participate
: This prospective observational cohort study was carried out according to the Code of Ethics of the World Medical Association (Declaration of Helsinki) and the study protocol was reviewed and approved by the Ethics Committee of the Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology (Protocol No.13 from Dec 06 2013). All participants (children’s parents) provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.