EC Gynaecology

Introduction and Objectives: Ectopic pregnancies account for 1.5 - 2% of all pregnancies in the first trimester in the United States. Methotrexate is considered the first-line medication for treating ectopic pregnancy. The effectiveness of treating ectopic pregnancy with a single dose of Methotrexate in clinical practice is based on a decrease in β-hCG levels by ≥ 15% between day 4 and day 7. This decrease in β-hCG during these days after a single dose of methotrexate has a positive predictive value (PPV) of 93%. The objective of our study is to evaluate the decline in β-hCG levels as a predictive factor for the success of ectopic pregnancy treatment with a single-dose methotrexate regimen.

Materials and Methods: This study included patients diagnosed with ectopic pregnancy who were admitted to the Gynaecology Department at University Hospital of Obstetrics and Gynecology "Queen Geraldine" Tirana, during the specified period from 2018 to 2021 and treated with a single-dose methotrexate regimen. Two tests were conducted. The first test analyzed changes in β-hCG levels between day 1 and day 4, while the second test analyzed changes in β-hCG levels between day 4 and day 7. The data obtained from both tests were analyzed using MedCalc software. To determine the statistical difference between the predictive values of the two tests, the Chi-squared test was used. The p-value was considered significant at < 0.05.

Results: The success rate of treatment with a single dose methotrexate regimen, without the need for additional doses of methotrexate or surgical intervention, was 70.7%. In the first test, the Positive Predictive Value (PPV) was calculated to be 85%, predicting treatment success with a decrease ≥ 15% in β-hCG levels between day 1 and day 4. The sensitivity and specificity were 64% and 73%, respectively. In the second test, the Positive Predictive Value (PPV) was calculated to be 89% for predicting treatment success with a decrease ≥ 15% in β-hCG levels between day 4 and day 7. The sensitivity and specificity were 82% and 75%, respectively. The p-value of 0.28 indicates that there is not statistically significant difference between the two tests. Therefore, the decline in β-hCG levels between day 1 and day 4 has approximately the same prognostic value as the decline in β-hCG levels between day 4 and day 7.

Discussion: From our study, it was found that a decrease ≥ 15% in β-hCG levels between day 1 and day 4 after treatment with a single dose of methotrexate regimen predicts treatment success in 85% of cases, without the need for additional interventions (medical or surgical). The fact that a decrease ≥ 15% in β-hCG levels can accurately predict the success of methotrexate treatment in less than 4 days makes it a valuable early indicator for predicting the success of ectopic pregnancy treatment.

Conclusion: According to our study, the success of a single-dose methotrexate regimen can be predicted three days earlier compared to the standard protocol prediction (Single-Dose Regimen). By predicting the success of treatment sooner, the treatment protocol can be adjusted more promptly. This allows for the administration of a second dose of methotrexate three days earlier if needed, potentially improving the outcome of ectopic pregnancy treatment.

 Keywords: Ectopic Pregnancy; Human Chorionic Gonadotropin (β-hCG); Medical Management; Methotrexate; Positive Predictive Value (PPV)

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