Comparative efficacy and safety of local and systemic methotrexate injection in cesarean scar pregnancy

OBJECTIVE To investigate the efficacy of methotrexate (MTX) injection in treatment of cesarean scar pregnancy (CSP). METHOD A randomized controlled study was performed in 104 CSP patients receiving either local or systemic MTX injection at the Peking Union Medical College Hospital from the year 2008 to 2013. RESULTS Complete cure was defined as regression of ultrasonographic findings and normalization of serum β-hCG within 60 days. It was regarded as delayed cure if additional dilation and curettage (D&C) was needed. The overall cure rate (complete cure plus delayed cure) was 69.2% versus 67.3% for local injection versus systemic administration (P>0.05). The median time for serum β-hCG remission and uterine mass disappearance after systemic administration (42 [21-69] days and 40 [20-67] days) were significantly lower than those receiving local injection (56 [24-92] days and 53 [23-88] days), with P=0.029 and 0.046, respectively. The mean pretreatment serum β-hCG (human chorionic gonadotropin) level and lesion size in cured group (21,941±18,351 mIU/mL and 2.9±1.3 cm, respectively) were significantly lower than those in the failed group (37,047±30,864 mIU/mL and 3.6±1.3) with P=0.038 and 0.044, respectively. CONCLUSION MTX injection is effective in CSP treatment. Systemic administration shows similar overall cure rate compared to local injection, but requires shorter time for serum β-hCG remission and uterine mass disappearance.