Inhibin b test

Hello lovely ladies. I have a question. I've been doing some research but unable to get a definite answer.

It's about day 3 inhibin b blood test. I've read that it's a test that's used to determine the number of eggs and years of fertility left. Some recommend the test, others say it's unreliable and hence not a recommended test to determine fertility.

Has anyone done the test? We're u able to get meaningful info from the results? Would I be wasting my money to do the test? It is expensive!