Ability of biparietal diameter to predict large for gestational age newborns. A retrospective cohort study

Abstract

Background: Predicting large for gestational age newborns is a medical action that requires technological tools with proven efficiency. Objective: To determine the predictive ability of biparietal diameter in large newborns for gestational age. Methodology: Retrospective cohort study that included 1959 Cuban pregnant women with a singleton pregnancy, with recruitment and pregnancy term between January 2009 and December 2017. In each gestational trimester, trophic conditions appropriate for gestational age (GAW) were compared and large for gestational age (GA) using central tendency (mean) and dispersion (range, standard deviation) statistics corresponding to the biparietal diameter. The 95% confidence interval (CI) for mean biparietal diameter difference was also calculated. In addition, an analysis of ROC curves was performed to determine if biparietal diameter and fetal weight predict large trophic condition for gestational age in the second and third gestational trimester. Data were gathered from the health area genetics registry book. Results: Biparietal diameter in the second and third trimester of gestation had an area under curve of 0.60 (95% CI: 0.54-0.65) and 0.59 (95% CI: 0.54-0.64) respectively. The established cut-off points (T2: 56.55 mm, T3: 81.55 mm) have a specificity and accuracy greater than 78%. Conclusions: Biparietal diameter and the Shepard and Hadlock V regression models showed ability to discriminate large for gestational age birth from adequate for gestational age birth from the second trimester of gestation onward, being more effective in the third trimester.

Keywords

• biometría fetal
• diámetro biparietal
• condición trófica
• peso fetal
• tercer trimestre del embarazo
• edad gestacional.