[1] Univ Warmia & Mazury, Coll Med, Sch Hlth Sci, Dept Midwifery, Zolnierska 14c St, PL-10561 Olsztyn, Poland
[2] Univ Warmia & Mazury, Coll Med, Sch Hlth Sci, Dept Nursing, Zolnierska 14c St, PL-10561 Olsztyn, Poland
[3] Prov Specialist Hosp Olsztyn, Dept Neonatol & Intens Therapy Newborn, Zolnierska 18 St, PL-10561 Olsztyn, Poland
[4] Nicolaus Copernicus Univ Torun, Ludwik Rydygier Coll Med Bydgoszcz, Dept Neonatol, Ul Ujejskiego 75, PL-85168 Bydgoszcz, Poland