You didn't mention if your endo did an initial battery of blood work before beginning your HRT. Not doing that would be negligent so I'm going to assume he did.
If your initial tests showed a healthy liver function then it's not out of the question to only order the blood work done on a 6 month interval. If you've seen him long enough, years not months, and he has a healthy time line of test results he may even suggest once a year.
My personal opinion is nobody should go more than six months without doing a liver function test at the very least. However, I have no insurance either so I know how unbelievably expensive it can be. I have a full battery of blood tests done once a year and a liver function twice a year. It's the only way I can afford it right now.
While there is no way to guarantee you won't develop a clot (DVT) there are precautions which can decrease the risk. Weight control, blood pressure control, not smoking, staying active and taking a lose dose aspirin every day are a few. I'm surprised your endo didn't discuss this in detail with you. I would really suggest talking to him about it..it is his responsibility to make sure you are told and understand everything, good or bad, pertaining to your treatment. In the meantime, you asked whether DVT has symptoms/signs or comes on suddenly and the answer is both. It can show symptoms such as numbness and pain in an extremity or a sign such as a hot area of skin and swelling. It can also form and break free with no symptoms/signs at all.
Scary stuff but ultimately very rare. Take your precautions and lessen the chance even more. The key is to be aware of your body and any changes, this applies as much to the potential for DVT to doing regular breast exams.
