No idea but it made me think of this:
(from a cracked article about strange beliefs about sex)
"As any teenage boy can tell you, you can't get pregnant from having sex just once. But your average horny teenager's got nothing on Papua New Guinean cultures like the Huli and the Arapesh, because they firmly believed that babies were the product of repeated intercourse. Repeated a lot. They didn't even know it was possible for a single sweaty night to lead to a baby -- they thought it took way more work than that.
For the most part, Huli and Arapesh beliefs were pretty close to being biologically accurate. They understood that sex led to pregnancy, and that babies were the result of man-juice meeting up with something inside the woman's body. So far, so good. The trouble was, they figured infants were actually constructed bit by bit out of sperm and menstrual blood. The man's sperm built the child's skin and bones, while the woman's blood took care of the internal bits. To be honest, Papua New Guinean pregnancies are just a bit too similar to Hellraiser for our comfort.
Now, if you figure that your average newborn is somewhere around 7 pounds -- and even if you figure that the woman takes care of the internal half -- holy shit that's still a lot of raw building materials for the man to provide. Clearly one night of bangin' isn't going to even come close to cutting it -- instead, these cultures believed that you had to have sex pretty much as often as the man could manage until you had squished together a healthy, viable sperm-and-blood baby.
The Arapesh themselves weren't necessarily all that happy about this situation. They said that there were two kinds of sex: the fun kind, and the kind you had when you wanted to get pregnant. Baby-making was an awful lot of work -- no matter how tired you were, or how not in the mood, you still had to get down to business. And they didn't even have candles and Marvin Gaye to help them out. "
https://www.cracked.com/article_20180_the-6-craziest-beliefs-entire-cultures-have-held-about-sex.html
