To my mind, it is a futile exercise. Births and Deaths are totally controlled by God and you cannot manipulate it with the assistance of a doctor or anyone for that matter. It is misusing astrology which is a sin. Even if I can tell you a best time for conducting the Cesarean, it does not help since most often the doctors get delayed and it cannot be done at the desired time. And even if you are able to do it, the time of birth is the time when the baby cries for the first time and that is definitely not in the hands of anyone.
And giving you a date is again totally meaningless since there are good times and bad times within a day which you cannot have any control on.
Do read my articles on http://navagrahastro.blogspot.in/ which will give you a better picture of how Astrology can be used in your life.