A cake for a lab tech who is retireing after 30 years at a health department.
He spends his days dipping urine and taking blood of pregnant women...
Test tubes, syringes, tubing, bandaids, litmus test strips etc. could be made and placed on a cake in a cute way.
From fondant, gumpaste, candy clay, etc.
There are a couple medical cakes in the galleries that have assorted 'doctor-type' items over a 2 tier cake with writing and even little people figures too. Very cute.
You could even have a tiny pregnant lady waddling up a path on the sides of a tiered cake towards your friend modeled on top with syringe in hand...
Sounds like a challenge, good luck!!
You might want to check out the cakewrecks blog for ideas. I think you can just google cakewrecks and it will come up. Be prepared to laugh hysterically!!!