I had a hair implant of about 2,400 follicular unit extraction (FUE) grafts febrery  2011. New hair is now visible in the frontal area, but it is sparse and I'm unhappy with the looks. Though most of the grafts were put in the frontal area of head, I had quite a few in the vertex area too, where so far I haven't seen any growth or changes. I'm now near the 6th month after surgery. What can I expect from this point on? What are my chances of having further improvement?


Each transplant causes microscopic scarring that can interfere with blood supply and possibly delay growth.
Some hairs can grow between 3 to 4 months but 75% of the patients have almost nothing then. Most hair starts to grow at 4 months with ongoing improvement between 6 to 12 months.Hair growth is still possible after six months. It has a cycle which leads to growth at about 3 months. Hair can skip a cycle, however, and growth is possible after that time.
With traditional strip graft follicular unit harvesting you should see hair growth easily in 3 to 6 months with a noticable and satisfying response in 9 to 12 months.If at that time you think you don't have the proper growth discuss this with your surgeon. With FUE grafts there is some expected loss of grafts but the number should still be small.

A brief EXPECTED TIME COURSE for hair growth after hair transplant

•immmediately after surgery- you can feel short transplanted hair , this hair doesn't grow at all
•one month after surgery- the transplanted hair falls out and it seems nothing was done.
•3-4 months after surgery- transplanted hair starts to grow as a fine soft hair.
•4-12 months after surgery- the transplanted hair gets thicker and fuller. Early on the FUE (natural grouping of hair that normally grows as a single, double, triple, rarely a quad) transplanted grows as a single hair, but will return to be a double/triple or whatever it was when transplanted. 
Some uncommon variations include hair that grows immediately after being transplanted (<5% of cases) and those who note continued improvement after the one year mark. If you are unhappy at 6 months, I would probably wait before doing another procedure. However, it sounds like you just need more hair and may need another session.