Once a woman was in labor; she was having a really tough time dealing with the pain. The doctor came to her husband and her and told them of a new experimental drug that allows the woman to transfer 25% of the pain to the father. The husband feels really bad for his wife so he decides they will try it.
The wife takes the pill and a few minutes later the husband says, "I don't feel a thing. You women are babies. Take another pill I can handle this." So the wife takes another pill. Same thing happens. Her husband tells her to take another pill. Same thing. By now she has transferred 75% of her pain to her husband. She is feeling a little pain but her husband is still feeling nothing. He is convinced that women are complete wuses. He tells her, "Take another pill. This isn't hurting me at all. Let me take all the pain away." So she does. Now they are both feeling great.
A few hours later, the wife gives birth to a beautiful baby boy. The next day they take their newborn son home, and there they find the mailman dead on the doorstep.