Hey I know this has been asked probably a million times. But while a MTF is doing Hrt exactly what blood test are used keep things in check.

Your GP or Endocrinologist will know what to check for, this isn't exactly something you need to know.  You just need to donate the blood for the tests.  But basically they are going to check your T levels, prolactin, cholesterol, potassium, sodium, Hemoglobin, hematocrit, White blood cell count, red blood cell count, glucose, etc.

There are often some local labs that will do a blood draw and give the test results, thus cutting down on some of the costs incurred.  Your provider would let you know what panels they want run.  The results can be released to the doctor or they can be given to the client who, in turn, delivers them to the doctor.  That is actually the route I go nowadays since it is easier to have a semi-annual blood draw done than have to go travel to my gynocologist (who has someone that can do the draw as well).  Saves me the co-pay on the office visit in addition to travel time.   

Back in the day, there were liver function tests as well as panels that looked at various estrogen levels in addition to the testosterone levels.  I may still have some of those in a file somewhere but more likely is that they are long gone...