Caesarean scar ectopic pregnancy: Experience from an Australian tertiary centre.

Background Despite the rising incidence of caesarean scar pregnancy (CSP), as yet there are no consensus or evidence-based guidelines for management. Aims To review diagnosis, treatment and management of all women with CSP over a 5 year period at Mater Mothers' Hospital, Brisbane, Australia. Materials and methods Retrospective cohort study of CSP between 2013-2018. Data reviewed included demographics, presenting symptoms, gestational age, ultrasound findings, human chorionic gonadotrophin levels, treatment success, complications, and if available, subsequent pregnancy outcomes. Results Twenty-eight women were treated for CSP during the study period. Initial diagnosis was delayed in ten (36%). Overall success rates of initial treatment were 22/28 (79%). Of the six cases of failed treatment, five had been treated with systemic methotrexate alone. All women requiring further intervention had fetal pole present, and 50% had fetal cardiac activity. Failure rate of systemic methotrexate alone was 5/11 (45%). Eleven women deemed appropriate for conservative management did not require further treatment or experience complications. Nine women had data available for subsequent pregnancies, of whom two developed placenta accreta. Conclusion This study provides data that may assist in guideline development and decision-making for management of CSP. Conservative management in carefully selected women appeared to be safe. Nearly half of women treated with systemic methotrexate alone required another treatment modality, suggesting a role for intralesional treatment, particularly in the presence of fetal pole +/- fetal cardiac activity. More than one in five women with documented subsequent pregnancies were diagnosed with placenta accreta.