Pregnancy: The prediction of ectopic pregnancy after in-vitro fertilization and embryo transfer

Data from 135 patients who suffered ectopic pregnancies andfrom 135 patients who progressed to singleton deliveries afterin-vitro fertilization and embryo transfer have been analysedretrospectively. The ectopic pregnancies represent all suchcases observed at Bourn Hall Clinic between 1983 and 1993. Thedelivered group was randomly selected from the same time period.The ectopic pregnancies included 20 heterotopic, eight ovarianand six bilateral tubal pregnancies; the remainder were singletontubal pregnancies. The aim of this study was to identify thevariables which differed systematically for the two groups ofpatients and to explore whether such variables could be usedto predict ectopic pregnancy at an early stage. The mean plasmaconcentration of human chorionic gonadotrophin and progesteronefor the ectopic pregnancy group was significantly lower thanthat for the singleton delivery group (P < 0.001). However,there was such a degree of overlap that it was impossible todevise a cut-off concentration for either hormone which wouldoffer a clinically useful predictor of ectopic pregnancy. Nevertheless,using the discriminant function analysis of these data, togetherwith the history of pelvic inflammatory disease, we could predictup to 90% of cases of ectopic pregnancy by day 23 after embryotransfer, long before ultrasound imaging would be useful.