Efficacy evaluation
The treatment efficacy was evaluated from three aspects, complete
remission (CR), drug resistance, and relapse. CR was defined as
normalization of β-hCG levels for at least three consecutive weeks.
Relapse was defined as elevated serum β-hCG level after CR without any
evidence of pregnancy. Drug-resistance was defined as serum β-hCG level
decreasing >10% over two courses of chemotherapy.