OBJECTIVE: To assess the association between gestational age estimated from the last menstrual period (GA(LMP)) or from the biparietal diameter (GA(BPD)), and the subsequent birthweight for gestational age. DESIGN: Population-based follow up study. SETTING: Of 21,936 pregnancies contained in the ultrasound database, 16,387 singleton pregnancies with a reliable last menstrual period date and an ultrasound examination between 12 and 22 weeks of gestation were included. MAIN OUTCOME MEASURES: Correlation between: 1) birthweight deviation (birthweight-expected weight for gestation); 2) birthweight; and 3) pregnancy length and (GA(LMP)-GA(BPD)). Relative risk of birthweight < 2,500 g and low birthweight for gestation (> 22% below normal weight) related to five levels of discrepancy between (GA(LMP)-GA(BPD)). RESULTS: (GA(LMP)-GA(BPD)) was not associated with deviation of birthweight related to GA(BPD). However the risk of low birthweight (< 2,500 g) and low birthweight for gestational age was significantly increased when (GA(LMP)-GA(BPD)) was > 7 days. CONCLUSION: A biparietal diameter smaller than expected from the last menstrual period date is mainly a problem of an error related to estimated time of ovulation. At the same time the relative risk of a low birthweight infant is slightly increased.
OBJECTIVE: To assess the association between gestational age estimated from the last menstrual period (GA(LMP)) or from the biparietal diameter (GA(BPD)), and the subsequent birthweight for gestational age. DESIGN: Population-based follow up study. SETTING: Of 21,936 pregnancies contained in the ultrasound database, 16,387 singleton pregnancies with a reliable last menstrual period date and an ultrasound examination between 12 and 22 weeks of gestation were included. MAIN OUTCOME MEASURES: Correlation between: 1) birthweight deviation (birthweight-expected weight for gestation); 2) birthweight; and 3) pregnancy length and (GA(LMP)-GA(BPD)). Relative risk of birthweight < 2,500 g and low birthweight for gestation (> 22% below normal weight) related to five levels of discrepancy between (GA(LMP)-GA(BPD)). RESULTS: (GA(LMP)-GA(BPD)) was not associated with deviation of birthweight related to GA(BPD). However the risk of low birthweight (< 2,500 g) and low birthweight for gestational age was significantly increased when (GA(LMP)-GA(BPD)) was > 7 days. CONCLUSION: A biparietal diameter smaller than expected from the last menstrual period date is mainly a problem of an error related to estimated time of ovulation. At the same time the relative risk of a low birthweight infant is slightly increased.
Authors: Karisa K Harland; Audrey F Saftlas; Anne B Wallis; Jerome Yankowitz; Elizabeth W Triche; M Bridget Zimmerman Journal: Am J Epidemiol Date: 2012-08-10 Impact factor: 4.897
Authors: Marija Simic; Olof Stephansson; Gunnar Petersson; Sven Cnattingius; Anna-Karin Wikström Journal: PLoS One Date: 2017-09-21 Impact factor: 3.240