The accuracy of single serum progesterone measurement in the diagnosis of ectopic pregnancy: a meta-analysis

Serum progesterone measurement has been advocated as a diagnostic tool inthe non-invasive diagnosis of ectopic pregnancy. To assess the accuracy ofa single serum progesterone measurement in the diagnosis of ectopicpregnancy, a meta-analysis was performed incorporating 26 studiesevaluating the performance of single serum progesterone measurement in thediagnosis of ectopic pregnancy. A distinction was made in the diagnosis ofpregnancy failure of any type versus viable intrauterine pregnancy and thediagnosis of ectopic pregnancy versus non-ectopic pregnancy. The reportedsensitivity and specificity differed between the studies. Since there was aclear negative correlation between sensitivity and specificity, summaryreceiver- operating characteristic (ROC) curves could be estimated. The ROCcurve for the diagnosis of pregnancy failure versus viable intrauterinepregnancy showed a good discriminative capacity. Single serum progesteronemeasurement could not discriminate between ectopic pregnancy andnon-ectopic pregnancy. It is concluded that serum progesterone measurementcan identify patients at risk for ectopic pregnancy, who need furtherevaluation, but its discriminative capacity is insufficient to diagnoseectopic pregnancy with certainty.