Woman's Hour - Every 4 mins a 15-24 year old is diagnosed with an STI - ÃÛÑ¿´«Ã½ Sounds

Woman's Hour - Every 4 mins a 15-24 year old is diagnosed with an STI - ÃÛÑ¿´«Ã½ Sounds
Every 4 mins a 15-24 year old is diagnosed with an STI
Why is there a rise of STIs in the 15-24 age group?