Estimated fetal weight. Maternal vs. physician estimate.

OBJECTIVE: To compare the accuracy of fetal weight estimation as determined by laboring, parous women vs. by a physician using abdominal palpation.

STUDY DESIGN: Four hundred seventy-one laboring, term, parous women underwent abdominal palpation by a physician and were subsequently asked to estimate the weight of their fetus, unaware of the physician's determination. Mean absolute error and percentage of fetal weight estimates within 10% of actual birth weight for both maternal and physician estimates were compared using Student's t test. Linear regression analysis was employed to determine whether maternal age, parity and race influenced the accuracy of the maternal estimation. In a similar fashion, level of physician training was analyzed to determine its impact on clinical fetal weight estimations.

RESULTS: There were no statistical differences in mean absolute error (331 vs. 324 g) or percentage of fetal weight estimates within 10% of actual birth weight (62% vs. 60.9%) between maternal and physician determinations, respectively. Maternal age, race and parity did not influence the woman's ability to accurately predict fetal weight. Greater physician experience did not improve clinical fetal weight determinations.

CONCLUSION: Parous women can subjectively estimate the weight of their fetus just as accurately as a physician using abdominal palpation. Neither maternal factors nor physician experience improves fetal weight estimations.