Hello, There is a relative risk of PID in women who use IUD. Chlamydia is a sexually transmitted infection. Regardless of what method of birth control you use you ought to go for protected sex, use of condoms is necessary. IUD protects you against pregnancy & not against STI. Avoid multiple partners. Since you are infected with Chlamydia visit ER at the earliest & get treated along with your partner. Your treating doctor will give a course of antibiotics to both of you. Neglect will cause PID to get worse in females & males may NGU, Epididymitis or proctitis. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Nupur K, General & Family Physician