title: [Birth weight and gestational age of newborns from Wielkopolski and Lubuski regions].
abstract: OBJECTIVE
  The correlation between the gestational age and the birth body weight are among others the basis of the estimation of newborn's maturity. Because of the acceleration of development and the decrease in the gestational age and birth body weight regarded as a limitation to newborn's survivalship there is a necessity of bringing up to date the existing reference systems.
  
  
  METHODS
  The main goal of this work is to modernize the reference system of birth body weight in relation to gestational age.
  
  
  METHODS
  The data of the birth body weight of 48,443 (25,225 boys and 23,218 girls) newborn, singleton children with a gestational age of 24-43 weeks were examined. Data was collected in 2001 and 2002 in Wielkopolski and Lubuski region. Values of the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentile were calculated. The analysis was carried out separately for both sexes. Additionally, because of lack of dimorphic differences until the 33rd week of gestation, percentile values were calculated for both sexes together in the partition of 24 to 33 weeks of gestation.
  
  
  CONCLUSIONS
  In comparison to previous reference systems, the obtained results showed a tendency for the birth body weight to increase.
authors.affiliation: Katedry i Kliniki Neonatologii, Akademii Medycznej im. K. Marcinkowskiego w Poznaniu.
authors.forename: Janusz
authors.initials: J
authors.lastname: Gadzinowski
authors.forename: Maria D
authors.initials: MD
authors.lastname: Kaliszewska-Drozdowska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kosińska
authors.forename: Jan
authors.initials: J
authors.lastname: Mazela
authors.forename: Bogumiła
authors.initials: B
authors.lastname: Stoińska
mesh_terms: D001724:Birth Weight / Q000502:physiology; D001827:Body Height / Q000502:physiology; D005314:Embryonic and Fetal Development; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011044:Poland; D012737:Sex Factors; D012959:Socioeconomic Factors