Single-dose methotrexate-based protocol for the treatment of caesarean scar pregnancy and successive pregnancy outcomes.

The incidence of caesarean scar pregnancy (CSP) increases in recent years. Yet, the best mode of treatment and its effects on successive pregnancies is not well established. The aim of this study was to investigate the success rate of single-dose methotrexate (MTX) in the management of CSP, and the outcomes of subsequent pregnancies in a retrospective cohort study. All women who were treated for CSPs between the years 2011 and 2019 were included. Treatment included systemic MTX and ultrasound-guided needle aspiration (UGNA) in cases with active foetal heartbeat. Overall, 34 women were diagnosed with CSP, of whom 31 were treated with systemic MTX. Twelve patients (38.7%) needed additional curettage or hysteroscopy. The only identified risk factor for failure of MTX-based treatment was time interval between the previous caesarean delivery and CSP (22 vs 34 months,  = 0.04). Twelve women had a subsequent pregnancy. Five pregnancies ended in term delivery, three in preterm delivery, three in abortion and one woman had a recurrent CSP. The study conclusion is that a single dose MTX with UGNA in cases of active heartbeat is an effective mode of treatment in cases of CSP with good sequential pregnancy outcomes. Longer time interval from the previous caesarean delivery was identified as a risk factor for failure of conservative management.