"How Much Will It Hurt?" joke

A woman suspected she was pregnant, so she went to see her doctor. After verifying that she was expecting, and since this was her first pregnancy, the doctor asked her if she had any questions.
"Well," she replied, "I am quite worried about the pain. How much will childbirth hurt?"
"That does vary from woman to woman and pregnancy to pregnancy," the doctor explained. "Besides that, pain can be difficult to describe."
"I understand that, doctor, but could you give me some idea of what to expect?" she asked.
"I'll try," the doctor said. "Grab your upper lip and pull it out a little."
"Like this?" she asked.
"A little more," replied the doctor.
"Like this?" asked the woman, pulling on her lip a bit more.
"No. A little more," instructed the doctor.
"Like this?" she asked, pulling her lip even more.
"Yes. Does that hurt?" asked the doctor.
"It hurts a little," she replied.
"Now stretch it over your head!" said the doctor.