1. Department of Neonatology, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
2. Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden
3. Health Research Institute, Faculty of Public Health, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
4. Department of Nursing, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania
5. Institute of Endocrinology, Lithuanian University of Health Sciences, 44307 Kaunas, Lithuania