Please help I-485 RFE

I am abit confused regarding to my I-485 RFE. Please help if you have experienced same situation before.

The RFE request to do a TB skin test and attach the x-ray report. If the TB test is clear (good), is there a need for x-ray? Also, I-693 form listed only do x-ray if your test meet certain conditions. The reson that I ask is because I am currently pregnnt, I can't do x-ray at this time. Otherwise I will do both to aviod any possible problems.

I have shceduled appointment this Friday for TB skin test, please help if you know anything about this subject.

Thanks much!