I had my first implant inserted in the UK in 2001 , and had it removed after 3 years . I only had one period during that time . After having a baby I had my second implant inserted , but started having periods every 1 to 2 weeks , which brought with them serious back pains . I had the stick removed but continue to have periods ( to date 11 in 21 weeks ) .

Based on the preceding passage, choose your answer for question What may be a reason for implanting a stick in your body ?
Pick your answer from: [I] For birth control .; [II] For a certain disease .; [III] For pain .; [IV] None of the above choices .;
The answer is:
[I]