Is PCR Test Advisable For Women With Recurring Miscarriages?

I am 27 year old. when I first time conceived, baby got dead after 5 month and when I conceived second time, baby got dead after 2 month. In both scenario, at first check up after 35 days of pregnancy, baby s heart bit was not detected. Now, to ensure better care, I have done hormones test and DNA test. All test are normal. Now I have done Mantoux test, which shows positive results. Now my doctor is advising for PCR test. What shall I do.?