Accuracy of estimated fetal weight in shoulder dystocia and neonatal birth injury.
OBJECTIVE
This study was undertaken to determine whether there is any difference in the rate of error of estimated fetal weight (EFW) in cases of shoulder dystocia compared with controls.


METHODS
Women whose delivery was complicated by shoulder dystocia were studied and compared with a control group matched for parity, race, labor type (spontaneous or induced), and birth weight (BW). Accuracy (%) was defined as [(EFW-BW)/BW] x 100. The primary outcome of the study was rate of EFW underestimation error 20% or greater.


RESULTS
During the 5-year study period, there were 206 cases of shoulder dystocia that met all study criteria. There was no difference in the number of patients that had EFW underestimation error 20% or greater (shoulder dystocia 9.8% vs control 12.8%; P = .38). There was also no difference in the number of patients that had EFW underestimation error 20% or greater between shoulder dystocia with and without injury (injury 8.3% vs no injury 7.1%; P = .79).


CONCLUSIONS
EFW underestimation error in cases of shoulder dystocia is an infrequent event and does not occur more often than in deliveries without shoulder dystocia.
Mehta
Shobha H
SH
Division of Material Fetal Medicine, Department of Obstetrics & Gynecology, Hutzel Hospital, Wayne State University, Detroit, MI 48201, USA. smehta@med.wayne.edu
Blackwell
Sean C
SC
Hendler
Israel
I
Bujold
Emmanuel
E
Sorokin
Yoram
Y
Ager
Joel
J
Kraemer
Todd
T
Sokol
Robert J
RJ
D000293:Adolescent; D000328:Adult; D001720:Birth Injuries / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D001917:Brachial Plexus / Q000293:injuries*; D016022:Case-Control Studies; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data; D004420:Dystocia / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D020567:Fetal Weight; D006801:Humans; D007231:Infant, Newborn; D008499:Medical Records; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D011237:Predictive Value of Tests; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012189:Retrospective Studies