In Aztec society, why would someone pray to Mictecacihuatl?

Mictecacihuatl (pronounced 'Mikt-eyk-as-see-wahl') was born from a sacrifice of an infant. I believe it was related to the ping of children through the fires of Molec in the Bible. This and the Aztec cult believed that killing children was a sacrifice and it saved the children from the pain of this world, and would yield more fertility with the mother. In these cults a woman was the main god and was worshiped with a ceremony where the child was "given" to the goddess for certain bestow of rights and sealed by it's death. They believe that there are some that still practice this in Mexico. These societies are secret and have signs and pwords to recognize each other.