I've been taking Cerazette for about a year, with no periods for the first nine months and then really irregular bleeding for a lot of the last three months - sometimes heavy, sometimes light, the odd day off and then back on again.
I had a pelvic exam and swabs on Friday and the doctor said I had a large cervical abrasion and has referred me to hospital. She also did a smear which would have been due in May anyway.
Obviously I'll know more after seeing the hospital doctor/gynae, but I can't help feeling worried. She said the usual treatment is lasering/cauterisation 
Has anyone else had this?