How do we feel about...

Steralisation. I read about women , of child bearing age, who ask to be sterilised and almost all doctors will say no due to the potential affects this may have should the woman change her mind. 
Is steralisation really the answer?....Or practising safe sex and being responsible? 
If steralisation is refused at child bearing age then does this cause more abortions? 
What should be the 'rules' around sterilising young women....Are they sure they won't change their mind?? Should a doctor have the right to refuse this??