The Impact of the Active Stage of Labor on Estimate Fetal Weight: A Prospective Cohort Study

Abstract

Objective: In the literature, there have been few data on ultrasound measurements during the active phase of labor. In this study, it was aimed to compare the accuracy of fetal weight estimation by ultrasound in terms of active phase of labor. Methods: This was a prospective cohort study at the obstetrics clinic of Esenler Gynecology and Children's Hospital in Istanbul. A total of 85 patients in active labor were included in the study. All pregnant women were evaluated for estimated fetal weight (EFW) by ultrasound evaluation, and cervical dilation and effacement measurements by pelvic examination, at most 24 hours before labor. Hadlock-4 formula was used for EFW. EFW and actual birth weight (ABW) and absolute errors of pregnant women in active labor were compared. Results: The mean EFW and ABW of the patients were 3161±482 and 3150±476 g, respectively. In terms of EFW and ABW, a finding in favor of the ultrasound was found. The error and error rates between EFW and ABW were found to be 234±191 g and 7.6±6.2, respectively. No significant difference was found in terms of these parameters (p>0.05). A significant and strong (0.80) correlation was found with estimated fetal weights and actual birth weights. Conclusion: Ultrasound can be used as a safe method to measure estimated fetal weight in the active phase of labor.