The Doctor & The Elderly Man.
"In fact, I do," said the old man. "After I have sex I am usually hot and sweaty, and then, after I have sex with her the second time, I am usually cold and chilly."
After examining his elderly wife, the doctor said, "Everything appears to be fine. Do you have any medical concerns that you would like to discuss with me?"
The lady replied that she had no questions or concerns. The doctor then said to her: "Your husband had an unusual concern." He claims that he is usually hot and sweaty after having sex with you the first time, and then cold and chilly after the second time. Do you know why?"
"Oh that crazy old jerk," she replied. "That's because the first time is usually in August and the second time is in January."