Initial hCG Levels in Ectopic Pregnancies After Embryo Transfer: Use of the Bayes Classifier for Risk Assessment

Area of Science:

• Reproductive Endocrinology
• Medical Diagnostics
• Biostatistics

Background:

• Distinguishing between ectopic and intrauterine pregnancies after embryo transfer is crucial for patient management.
• Early detection of ectopic pregnancy can prevent severe complications.

Purpose of the Study:

• To evaluate the effectiveness of the Bayes classifier in differentiating ectopic from intrauterine pregnancies.
• To assess the utility of early human chorionic gonadotropin (hCG) levels in this differentiation.

Main Methods:

• Retrospective chart review of patients undergoing in vitro fertilization.
• Analysis of human chorionic gonadotropin (hCG) levels between days 12-20 post-oocyte aspiration.
• Application of statistical analysis including mixed effects model and Bayes classifier.

Main Results:

• hCG levels in ectopic pregnancies were significantly lower (14% of control group, p<1×10-15).
• A Bayes classifier threshold of <18 IU/L indicated >75% probability of ectopic pregnancy.
• No significant differences were found based on endometrial thickness, embryo transfer type, or oocyte source.

Conclusions:

• The Bayes classifier serves as a valuable tool for alerting healthcare providers to potential ectopic gestations.
• Early hCG monitoring combined with the Bayes classifier can improve diagnostic accuracy.