Regular Senior Resident In Delhi Govt Regd Maternity Leave

I am working as a regular senior resident in a delhi govt hospital. I was working on adhoc basis from may 2013 and was regularised on dec 2013 for a 3 year tenure period renewable every year (including the period preceding december).
I had to take medical leave ( mostly as unpaid leave) for a period of around 130 days in 2014 in broken intervals. I am on maternity leave since october with joining in early april. My second year tenure ends in may, i donot want to renew my tenure for the third year. Do i have to give one month notice period in this case? Can i just send a non renewal of contract or do i have to resign? Also am i eligible for taking my earned leaves after the maternity leave? How many earned leaves am i eligible for?

I am posted as a regular senior resident, am not on adhoc basis. Also the hospital authorites say they have no information regarding these.

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I understand you are appointed in a 'tenure post' for 3 yrs. but renewal every year by 'mutual consent'. Your 2 yr. will be completed by end of May 2015 and you are going to say NO to continue beyond May 2015. In other words, you don't want to continue beyond May'15. As Mr.Mehta pointed out all matters related to your service conditions should have been spelt out in your appointment letter or agreement with the hospital including that of ML or resignation/termination etc. If no such terms & conditions are given to you, better issue an advance notice atleast before one month indicating your inability to continue. Reg.leave etc. you have to seek clarifications in writing from the Hospital only.