Recently there is a bad smell when I masturbate/ have sex

It might sound strange, but make sure you have not something stuck inside your vagina. An old tampon (it happens!), part of a toy or condom.

If not, no might want to visit your doctor.

Take care!

I actaully agree with the post above me, there is a possibility of a foreign object in there by the way you explained your activity. But I am more concerned with it being way more serious like an infection in your womb. Now I know you are embarrassed but there is a chance especially with an IUD that you have an infection and one that is in your womb rather than your vaginal canal which means if you don't get it take care of you can become infertal which to most women is serious and important. If you had an infection in your womb it would explain why you don't have other symptoms and why it only happens when you are having something entering and exiting your vagina. Because your cervix which is very small would be keeping that infection in the womb or your tubes and only letting an odor not fluids out. You could very well have PID. You may also have an STD or something other than an infection. Either way you need to go to the OB/GYN who specializes in women's problems such as these and get checked out, unless you really do have a tampon left up there!

P.S. With the IUD in there I would not risk it!

Is there a chance that your partner could have had sex with someone else? It sounds like an STD. The one I am thinking of starts with a T and I can't pronounce it. I have it. My boyfriend cheated when I was pregnant and it caused lots of problems! Best to see a doc.

Thanks for the replies. I ended up feeling inside as suggested and was horrified when I felt something!!! I started pulling and got incredibly bad sharp pains and realised it must be the Mirena I was pulling at!!!!!!!!! It wasn't the strings that would normally be there but hard plastic... I went to the doctor straight after that and yes the Mirena IUD was half hanging out causing PUS inside the cervix which was the bad smell. SO gross!
I am really annoyed and disappointed now. I got the Mirena put in a little over a year ago and it was the worst pain I ever felt in my whole life but I loved it so much that I never had to worry about the pill or anything and now it is gone and there is no way in hell I am going through the pain of getting another one
damn it. But glad the smell problem will be cleared up soon!!!! thanks!