It is common after pituitary surgery to lose a hormone or two. Usually it is thyroid and growth hormone first and then others may or may not go.
I would get a copy of the tests to see what the doctor tested and see what the levels are. Hopefully too the endo will test all your hormones and keep and eye one you as post op pituitary you have to monitor your hormones regularly as well as image just in case the lesion comes back.
Do you know what type of tumor you had?
I am 47 years & had pit tumor removed in early 2013. I've had low thyroid & testosterone levels since. For the low-T, my endocrinologist injects me with testosterone replacement hormone Nebido (4 ml). It usually lasts 3-4 months before I had to be injected again. Not long after the first Nebido injection, I started drinking extract of soursop leaves (recommended by another pit tumor patient). After 2-3 more Nebido shots while taking soursop leaf extract, I was able to keep my testosterone level stable (within range) & did not need Nebido for the next year. So a combo of medicine & herbs actually works, but I had to contually drink the extract. Once I slacked off, my low-T returns & now I have to redo the process again. This time I'm trying it with Sustanon (1 ml), another hormone replacement not as potent as Nebido & combining it with increased soursop extract intake. Hope this helps & please ask me any other questions. I don't mind sharing & helping fellow patients.