The first participant was enrolled on Feb 16 , 2006 , and the last study visit for the present analysis took place on Dec 10 , 2010 ; 5752 women were included in the total vaccinated cohort ( n = 2881 vaccine , n = 2871 control ) , and 4505 in the according-to-protocol cohort for efficacy ( n = 2264 vaccine , n = 2241 control ) .