Fascinating entry from Wikipedia on the Aztec’s view of childbirth, including their belief that women who died during childbirth became malevolent spirits,
In Aztec mythology, the Cihuateteo or “Divine Women,” were the malevolent spirits of women who died in childbirth. They were likened to the spirits of male warriors who died in violent conflict, because childbirth was conceptually equivalent to battle in Aztec culture. According to tradition, a woman in labor was said to capture the spirit of her newborn child similar to the way a warrior captures his opponent in battle. These spirits are also associated with the west, the place where the sun sets each day.
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When an Aztec woman experienced childbirth, it was seen as a violent and laborious effort likened to the intensity of battle. It was believed that the child was sent down to the earth by the gods, and the woman had to fight and struggle in order to bring it into the world. The newborn child was seen as a sufficient reward if she was successful and emerged victorious from her “fight” with the gods, but if she lost and proved unsuccessful, then she died and her soul underwent transformation into a cihuateotl.
In the case of the death of the woman, special funerary practices were carried out, as the body of a woman who had died in childbirth was believed to possess special powers and magic following the departure of the soul from the body. In these special practices, the body was guarded fiercely by an armed entourage that included the widowed husband, his friends, all the midwives, and old women. This was deemed necessary due to the need to protect the woman’s human remains from male warriors. Parts of the body believed to be especially potent relics for warriors were the left middle finger and the hair. According to Aztec belief, “these relics had magical power and, if placed on their shields, would make the warriors brave and valiant, give them strength, and blind the eyes of their enemies.”