OBJECTIVE: To provide a new outcome measure for pregnancy specifically related to the individual. DESIGN: Computer analysis of physiological factors affecting birthweight. SETTING: Two provincial teaching hospitals (University and City Hospitals, Nottingham) and an associated district general hospital (Derby City Hospital) serving a defined catchment area in the East Midlands. SUBJECTS: All women delivering in the above hospitals since the start of computerised obstetric records: 31,561 women with gestational age verified by early pregnancy ultrasound scan data. MAIN OUTCOME MEASURES: Calculation of the predicted birthweight taking into account maternal and fetal physiological factors. Derivation of the individualised birthweight ratio (actual birthweight divided by predicted birthweight expressed as a percentage) for each individual baby. RESULTS: The individualised birthweight ratio redefines as normally grown 41% of babies below the 10th centile of crude birthweight for gestation. Other babies previously regarded as normal are redefined as growth retarded. At the upper end of the distribution 46% of those above the 90th centile of birthweight for gestation are redefined as normally grown. CONCLUSIONS: The predicted birthweight can be calculated for an individual pregnancy at a given gestation. The standardised comparison between this predicted birthweight and the actual birthweight is a more logical reflection of the normality of intrauterine growth and therefore more logical as an outcome measure for pregnancy than crude birthweight for gestation.
OBJECTIVE: To provide a new outcome measure for pregnancy specifically related to the individual. DESIGN: Computer analysis of physiological factors affecting birthweight. SETTING: Two provincial teaching hospitals (University and City Hospitals, Nottingham) and an associated district general hospital (Derby City Hospital) serving a defined catchment area in the East Midlands. SUBJECTS: All women delivering in the above hospitals since the start of computerised obstetric records: 31,561 women with gestational age verified by early pregnancy ultrasound scan data. MAIN OUTCOME MEASURES: Calculation of the predicted birthweight taking into account maternal and fetal physiological factors. Derivation of the individualised birthweight ratio (actual birthweight divided by predicted birthweight expressed as a percentage) for each individual baby. RESULTS: The individualised birthweight ratio redefines as normally grown 41% of babies below the 10th centile of crude birthweight for gestation. Other babies previously regarded as normal are redefined as growth retarded. At the upper end of the distribution 46% of those above the 90th centile of birthweight for gestation are redefined as normally grown. CONCLUSIONS: The predicted birthweight can be calculated for an individual pregnancy at a given gestation. The standardised comparison between this predicted birthweight and the actual birthweight is a more logical reflection of the normality of intrauterine growth and therefore more logical as an outcome measure for pregnancy than crude birthweight for gestation.
Authors: Kjersti Aagaard-Tillery; Catherine Y Spong; Elizabeth Thom; Baha Sibai; George Wendel; Katharine Wenstrom; Philip Samuels; Hyagriv Simhan; Yoram Sorokin; Menachem Miodovnik; Paul Meis; Mary J O'Sullivan; Deborah Conway; Ronald J Wapner Journal: Obstet Gynecol Date: 2010-03 Impact factor: 7.661
Authors: S Zucchini; E Cacciari; A Balsamo; A Cicognani; D Tassinari; E Barbieri; S Gualandi Journal: Arch Dis Child Date: 2001-04 Impact factor: 3.791
Authors: Chibuike G Iruloh; Stephen W D'Souza; William D Fergusson; Philip N Baker; Colin P Sibley; Jocelyn D Glazier Journal: Pediatr Res Date: 2009-01 Impact factor: 3.756