Which of the following factors does NOT contribute to the biological etiology of PMADs?

Genetic factors play a crucial role in the biological etiology of perinatal mood and anxiety disorders (PMADs) by influencing an individual's susceptibility to these conditions. Research has shown that genetics can impact neurotransmitter systems, hormonal balance, and stress response mechanisms, all of which are relevant to the onset of PMADs.

On the other hand, oxytocin, progesterone, and prolactin are hormones that fluctuate during the perinatal period and have been implicated in mood regulation. Changes in oxytocin levels, for example, are associated with bonding and emotional regulation, while progesterone and prolactin also influence mood and can contribute to the development of PMADs.

In summary, while genetic factors provide a foundational biological framework for understanding PMADs, the hormonal changes represented by the other choices directly impact mood and emotional well-being during the perinatal period. Thus, genetic factors would not be characterized as a contributing factor to the biological etiology in the same way that the other options do.