I am 23 years male. recently I was approached by a man whose age is 43 and his wife age is 34. He said that he has male impotency and can not make his wife conceive. They also said that they tried test tube baby but can not succeed .they said that the doctor advised his wife to have sexual intercourse with younger man of age 20 to 24 because high concentration of sperms will be present at this age. I am ready to have intercourse with her. But I want to know that this type of medical conditions really available? And how many times and when I should have intercourse with her?