It is sexually transmitted in the cases we are talking about here.
It doesn't have anything to do with other infections. Its just a bacteria that can be transmitted through oral and genital sex.
AJ
Thank you auntiejessi...but I didn't understand ANY of that. How would one acquire this infection? Through another one that wasn't treated the right way?
Nope, I lied lol.
http://pathmicro.med.sc.edu/mayer/myco.htm
http://www.emedicine.com/med/topic2340.htm
Decent article, but I couldn't find any better ones.
AJ
What exactly is Ureaplasma?
In addition to the above excellent advice, the next step you can take if you really have a resistant strain is to do antibiotic susceptibility testing.
Those tests can be done from here:
http://www.mycoplasma.uab.edu/intro.htm
You'd have to stop taking antibiotics for a little while to get a good culture, but after that you would know exactly which antibiotics would work.
If the second antibiotic you took was Cipro (pretty common), that and Doxycycline are the two most likely to fail due to resistance. Of course, that's what most doctors prescribe anyway.
So check the above factors first, and if you're not getting reinfected, then I'd go ahead and do these tests and be done with it once and for all.
The other thought is if you have a partner and if she/he hasn't been treated. If that's the case, that's why you still have it, and your partner would also need to be treated.
AJ
If doxy is not working for you, they need to stop increasing the dosage, and start a new treatment regimen.
Did you test for gonorrhea and chlamydia?
AJ