Pertho is the rune of luck, chance and merrymaking, though it has come to represent creation as well. No other rune has had more misconceptions applied to it than Pertho, perhaps is fitting considering its original meanings. P is not a character that often precedes a word in the Germanic languages, therefore it is assumed that the name is derived from a foreign word. This is where people seem to want to apply random concepts without any historical evidence.
It has been suggested that the name of this rune derived from Slavonic word pizda, or womb, though this is quite humorous when applied to the above rune poem, it is also obvious that it is incorrect. The other mistake people often make is in assuming that because there is disagreement over the original meaning of this rune that it can represent "mystery" or the blank rune. With a little analysis one may quickly realize that a blank character in a written language is, well, quite stupid. One cannot write nothingness, and though the Norse were often though of as barbaric, they were not known for their foolishness.
The concept of a blank rune came about though a shining example of new age literature called the Book of Runes, by Ralph Blum. It was written in 1982 and continues to exasperate anyone attempting an historical study of futhark. In his text he blatantly admits that he received a rune set from another person, without instructions. So one night he was suddenly inspired with their meanings, the most interesting of which is the addition of the blank rune. A beautiful story really, but his interpretations are not in sync with the academic community or the rune poems themselves, which are considered to be the definitive source on the interpretations of the runes. It is interesting to note that prior to this publication on runes, Blum was most known for his books on UFOs and extraterrestrial contact. Be that as it may Blum's Book of Runes and his subsequent texts have become one of the most quoted works on runes. They are especially popular with the new age crowd, but shunned by most historians and reconstructionalists.