Post partum psychosis was dreamed up as an excuse after the Yates atrocities. Yes, there has been an entity referred to as post partum blues or post partum psychosis, but until the Yates killings, I never heard of mothers killing their kids and claiming this as an excuse to avoid responsibility for something like this. I have delivered many babies and followed up with mothers, and have seen what we used to term postpartum blues. Not ever seen manifestation 11 months after delivery. Most like drug induced altered state of consciousness.
Do you know if drugs were involved in the Yates case?