Abstract
Objective: To study the patterns of serum bhCG levels on days 1-4 and days 1-7 after single-dose methotrexate injection (MTX) for ectopic pregnancy (EP) and to determine the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the best cut-off points for the "percentage of fall'' in serum bhCG levels for predicting a successful outcome.
Patients and methods: This is a retrospective cohort study including forty-nine consecutive patients treated with single-dose MTX (50 mg/m(2)). We analyzed patterns of falling in bhCG levels on D1, D4 and D7 of follow up. Our main outcome measures included the overall success rate, the "percentage of fall'' variable of serum beta hCG levels on D4 and D7 and the best cut-off point for the "percentage of fall'' that predicts a successful outcome.
Results: The success rate of single-dose MTX treatment in EP was 77.5%. A cut-off "percentage of fall'' in beta hCG serum levels on D1-D7 of >= 33% has the best sensitivity (96%) and PPV (85%) for predicting a successful outcome. This is out performing any cut-off on days 1-4 and comparable to the standard D4-D7 protocol.
Conclusions: After single-dose MTX injection for EP, the use of D1 to D7 follow up protocol outperforms that of D1 to D4; with possible elimination of D4 routine beta hCG blood draw. A cut-off "percentage of fall'' in beta hCG serum levels on D1-D7 of >= 33% has the best sensitivity and PPV. (C) 2014 The Authors. Production and hosting by Elsevier B.V. on behalf of Middle East Fertility Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-ncnd/3.0/).