One of the most important points that Bornstein makes in this article is that only a small percentage of postpartum depressions have something to do with "natural" hormonal changes. In fact, this article states that most postpartum depressions are not isolated forms of depression, and at least some of the symptoms may be present during the life span years before and/or after pregnancy, indicating that delivering a baby may not be the underlying cause of the depression. Furthermore, the risk factors for postpartum depression are the very same as for any type of depression, namely a history of depressive episodes, past and current life stresses, a history of trauma and abuse, interpersonal conflict with primary support group, lack of social support and poverty.
Because only a small number of women get treatment for their depressive symptoms before their baby is born, even when the symptoms are present during the pregnancy, it is important for people to understand that treating depressive symptoms early can mitigate, and hopefully prevent subsequent suffering. The good news is that there are a number of ways to treat the various symptoms of depression during and before pregnancy, and not all of them mean having to take a pill. Studies show that non-pharmacological treatments such as exercise, mindfulness practices, increasing one's support network, and psychotherapy can all decrease depressive symptoms. It is also important to keep in mind that if one's depressive symptoms are such that pharmacological interventions are indicated, there are currently a number of medications that have been approved for use in pregnancy.