however , the half life of hcg was related to the type of operation : after conservative operation of ectopic pregnancy the half life of hcg was greater than after tubectomy ( 41.4 +/- 1.9 sem hours versus 33.4 +/- 2.0 hours ) , possibly due to lack of complete removal of trophoblast tissue .
C0543467
operation
C0015250
complete removal