OP24.07: Systemic methotrexate as an effective treatment for non‐viable caesarean section scar pregnancy

Abstract

There is no consensus on the management of caesarean scar ectopic pregnancy (CSP). We aim to identify factors affecting treatment outcome using systemic methotrexate. Cases of CSP were reviewed retrospectively in a teaching hospital from January 2011 to December 2013. The diagnosis was based on the following sonographic criteria: an empty uterus, an empty cervical canal and presence of the sac in the anterior part of the uterine isthmus. Cases were classified into 2 groups; Group A - successful treatment by systemic methotrexate (im MTX) 50 mg/m3 alone with complete resolution of serum hCG; Group B - failure of im MTX as evident by persistently elevated serum hCG requiring additional treatment. In addition, a search of English-language literature was performed in PubMed using keyword ‘caesarean scar pregnancy’, from year 2009 to 2013. Cases with systemic MTX alone as initial treatment were included in the analysis. The association of maternal age, number of C/S, time from last C/S, pre-treatment serum hCG level, fetal cardiac activity, maximum sac diameter, time for serum hCG resolution in both groups were analyzed using Mann-Whitney U test and Barnard's Exact test as appropriate. Fourteen cases of CSP were diagnosed during the studied period with 12 cases used systemic MTX alone as initial treatment. About 300 cases were identified in PubMed and 7 cases satisfied the inclusion criteria. Total 19 cases were included for analysis, 14 cases (74%) with successful treatment with systemic MTX were in group A and 5 cases (26%) were in group B. All cases in group A had single dose systemic MTX as the treatment regime. Analysis showed that fetal cardiac activity was associated with failed treatment by systemic MTX (p = 0.04). All other factors were not useful in predicting the treatment outcome (p > 0.05). Systemic methotrexate is an effective treatment for non-viable caesarean scar ectopic pregnancy.