Lets say I have a bond portfolio that i have hedged by shorting a certain number of futures.
In case all rates increase over 3 months, but short term rates increase less than the medium term rates and medium term rates increase less than long term rates.
What effect will this have on the hedge??
Regards
It depends on the distribution of durations in your portfolio, and the duration of the futures contracts you used for the hedge.
I would love to read your answer in greater detail 
Sounds like you have a bear-steepener - if your futures represent a short-bullet portfolio, your hedge should outperform relative to your portfolio ie the increase in your futures value > decrease in your portfolio