Overestimation of fetal weight by ultrasound: does it influence the likelihood of cesarean delivery for labor arrest?
OBJECTIVE
We sought to determine whether the overestimation of ultrasound-derived estimated fetal weight (EFW) is associated with increased diagnosis of labor arrest.


METHODS
This is a historical cohort study of nulliparous women with term pregnancies who underwent bedside ultrasound examination for EFW before labor induction. Labor outcomes of women with EFW overestimation > 15% the actual birthweight were compared with those with EFW not overestimated.


RESULTS
Overestimation of EFW occurred in 9.5% of cases (23/241). The rate of cesarean delivery (CD) for labor arrest was higher for those with EFW overestimation (34.8% vs 13.3%; P = .01) even though there were no differences in length of the induction duration. After adjusting for confounding factors, EFW overestimation remained associated with CD for labor arrest (odds ratio, 4.8; 95% confidence interval, 1.5-15.2).


CONCLUSIONS
Our finding suggests that an overestimation of EFW may be associated with a lower threshold for CD for labor arrest.
Blackwell
Sean C
SC
Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA.
Refuerzo
Jerrie
J
Chadha
Rati
R
Carreno
Carlos A
CA
D000293:Adolescent; D000328:Adult; D002585:Cesarean Section / Q000706:statistics & numerical data*; D015331:Cohort Studies; D003951:Diagnostic Errors; D005260:Female; D005320:Fetal Macrosomia / Q000000981:diagnostic imaging*; D020567:Fetal Weight; D006801:Humans; D007751:Labor, Induced; D007744:Obstetric Labor Complications / Q000000981:diagnostic imaging; D010298:Parity; D011247:Pregnancy; D016216:Ultrasonography, Prenatal / Q000592:standards / Q000706:statistics & numerical data*; D055815:Young Adult