While the majority of patients were aged between 30 and 50, Dr Wilson said men as young as 20 did approach the clinic from time to time but were turned away if they were yet to have children. "They've got a lot of life to live," he said. "There's guys in their 20s with four kids - that's a no-brainer."
In other cases men older than 50, with younger partners, also wanted a vasectomy.
Dr Wilson said he never questioned couples who had been together for 10 or 15 years and had no children but did not want any.
A lot of men delayed vasectomies because of worry and arrived at the clinic very nervous, he said.
A lot of effort is put into making them feel relaxed, including allowing them to choose music to play during the procedure.
Others had heard vasectomies increased the risk of prostate cancer - a myth that had no medical backing, Dr Wilson said.
Generally men who got vasectomies were the same ones likely to be registered with a GP and visit them regularly.
"You can't get diagnosed with cancer unless you go to a GP," he said.
It was important to chose an experienced doctor who had done a lot of vasectomies. "You want experience because the risk is another child," he said.
Dr Wilson also said he performed about five vasectomy reversals a year which were most successful within 10 to 12 years of the vasectomy.
