Abstract
Objective Frozen section examination is a rapid method for identifying products of conception
in endometrial curetting, yet its accuracy is inconclusive. The purposes of this study
is to determine the accuracy of frozen section analysis of endometrial curetting in
pregnancies of unknown location, and to verify the relation of β-human chorionic gonadotrophin
(hCG) level and endometrial thickness to the assessed accuracy.
Methods We reviewed data from January 2009 to December 2014 of diagnostic curettages from
women with suspected ectopic pregnancies sent for frozen section examination at a
medical center. A frozen section diagnosis was considered accurate if it concurred
with the final pathologic diagnosis.
Results Of 106 frozen section studies, the diagnosis was accurate in 94 (88.7%). Of 79 specimens
interpreted as negative on frozen sections (no products of conception noted), 9 (11.4%)
were positive on final pathologic review. Three of the 27 (11.1%) specimens interpreted
as positive by a frozen section failed to demonstrate products of conception on a
final pathologic section. The sensitivity of frozen sections in the diagnosis of ectopic
pregnancy was 72.7%, specificity 95.9%, positive predictive value 88.9%, negative
predictive value 88.6%, and accuracy 88.6%. A statically significant correlation was
found between β-hCG level and high accuracy of the frozen section technique (p < 0.001). No correlation was found between endometrial thickness and the accuracy
of the frozen section technique.
Conclusion The accuracy of frozen section examination was high and was found to correlate with
β-hCG level, but not with endometrial thickness.
Keywords
ectopic pregnancy - frozen section - pregnancy of unknown location - β-hCG - endometrial
thickness
