Person period format, discrete time models , event history

Hello
I am working on calendar data of DHS which has data of each women stored in a string format for last five years. For each variable for a women has 80 string variable, each letter in string represents an event in women for each month for the past five years. For example use of contraception of women is represented for a random women as follows "vcal_1
333BPPPPPPPP00333330BPPPPPPPP000000000000000000000 0000000000000000000" where P represents pregnancy and 0 represents non use of contraception etc.,. I was reading a paper on modelling these kind of data into a event history discrete time models for which this data need to be transformer into a person-period format. So can some please do let me know who convert this type of data into person period format.


Thanks in advance.