Indeed, in a pharmacological mouse model of PP, Humby and colleagues showed increased CCN3 expression in the brain tissue of new mouse mothers that were administered a steroid sulfatase inhibitor (Humby et al., 2016) (used to mimic maternal steroid sulfatase deficiency, which has been proposed as a potential risk factor for PP (Davies, 2012)). This evidence concerns the gene STS and hyperinsulinemic hypoglycemia, familial, 4.