Body mass and body length of warsaw’s newborns

Introduction. In the opinion of WHO experts, the norms of somatic development established on the basis of Multicenter Growth Reference Study (WHO MGRS or WHO-GS), conducted between years 1997–2003, are universal and should be used as an assessment tool of the somatic status and development of newborns. This statement enables recommending the WHO standards, defining “what the development of children should be like”, to be implemented in Poland. Study aim. To design norms of body mass vs. body length for Warsaw newborns and to compare the measurements of newborns with WHO MGRS norms. Material and Methods. Body mass and body length data of 3052 male and 2825 female single pregnancy newborns from 13 Warsaw hospitals, born from May to December 2013 were used. Results. About 91% of male newborns and about 88% of the female ones were below the 3rd percentile of WHO weight-body length norms. When the respective norms proposed by us were used, all data fit the 3rd – 97th percentile range, and the percentages below the 3rd or above 97th percentiles did not significantly deviate from the expected 3%. However, some hospitals differed significantly from one another with respect to body length and to body mass vs. body length of both male and female newborns, but no significant differences in body mass were detected. Conclusions. In order to ensure appropriate assessment of newborns, all maternity wards in the country should use a uniform method of taking measurements at birth and then one selected tool for the assessment of newborns, for example WHO MGRS, should be implemented in all Polish clinics.