That sounds terrible! I am so sorry to hear that. I have to say, your situation is unique, as serratia is a less common infection, and you usually only get infected with it in a hospital setting, or if you have a weakened immune system. Further, you had the infection at an unusual site for this sort of thing, your cervix. Ive never seen serratia infection of the cervix, so I can only make an educated guess. If the infection was months ago, and you have a normal healthy immune system, then you are probably not contagious. Also the likelihood of transmitting serratio through sex is probably low. However, since your boyfriend has leukemia, especially if he is actively sick with it or undergoing chemotherapy, he will have a weakened immune system, and is at risk of catching it. I strongly encourage you to use a condom every single time you engage in sexual intercourse, just in case. I also encourage your boyfriend to ask his oncologist (cancer doctor) if its okay to have sex in this situation. If your boyfriend is fully recovered from leukemia, and has been in remission for at least a year, then it is unlikely he will contract serratia from you. Hope that helps! The response written above is a medical opinion, and does not substitute an evaluation by a medical professional. I cannot guarantee accuracy in my answer, especially when I cannot physically evaluate you, and do not know your past medical history, all of the medications you are on, your lifestyle habits, etc; therefore I cannot be held liable for any consequences that occur as a result of my opinion.