Over the course of the next 40 days, the brain-baby migrates from its father's head to his chest to his belly to ... well, you know where this is headed. Once the baby has reached its father's junk, there's a period of a little more than a week where he's a loose cannon, ready to shoot a tiny baby into any willing female companion. This is when the sexy happens, and the baby takes a ride through its father's dong and into its mother's body, just like that tunnel in Space Mountain.
You'll note that the male pregnancy ends with an orgasm, while the female pregnancy ends with hours of labor. This proves that life isn't fair, and class is now dismissed.
"This is BULLSHIT!"
So Why Do They Believe It?
If we're going to look at these weird-ass beliefs from various cultures around the world, we should take a moment to figure out why anyone believes them. After all, most weird beliefs exist because, well, they work.
In this case, it solves a problem that the actual scientific understanding of pregnancy brings: that the responsibility for a pregnancy is on the woman alone. Women have to take prenatal vitamins, avoid alcohol, eat responsibly, give up smoking ... while guys could squirt and bolt, and it wouldn't affect the baby one bit. Physically, anyway. Whereas the Malay belief says to the man, "You also carried this baby for over a month."
And after so long, it just doesn't fit back in. So no refunds.