This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Which of the following procedures is associated with maximum chance of re-canalization during surgery for reversal of tubal ligation? 
Select and explain. 
A. Isthumo- isthmic anastomosis, B. Isthumo- ampullary anastomosis, C. Ampullo-ampullary anastomosis, D. Cornual obstruction
A: Isthumo- isthmic anastomosis
Answer: A: Isthumo- isthmic anastomosis 
Explanation: When re-canalisation of tubal ligation is done, the isthumo-isthmic anastomosis has given the best results compared to the other methods of anastomosis. Ref: A. Laparoscopic tubal sterilization reversal and feility outcomes journal - K Jayakrishnan and Sumeet N Baheti; B. Examination Obstetrics & Gynaecology by Goh & Flynn 3rd edition, Pages 44-52; C. Postgraduate Gynecology By B. Presannakumari; 1st edition, Pages 180-82