Hi,
Tubal ligation as you probably know already is a procedure of female sterilization which is done on the
fallopian tubes by division of the tubes such that they are no more in continuity. It is an effective
procedure with a low failure rate. By failure I mean that the tubes get reconnected by themselves and thus
sterilization fails and the woman can become pregnant.
In your post, you have asked that you want your fiance to become pregnant and therefore wonder if the body can
automatically develop a bypass. Well this is known to occur but is so rare in occurrence that you may not bank
upon it to get the tubes patent and continued.
Thus you must consider going back to your doctir to get this reveresed since there is practically no chance of
the tube getting reconnected to each other.
I hope I answered you satisfactorily.
You may ge more information at:
http://en.wikipedia.org/wiki/Tubal_ligation