The cause of PPD is unknown. Hormonal and physical changes, personal and family history of depression, and the stress of caring for a new baby all may contribute to the development of postpartum depression. Evidence suggests that hormonal changes may play a role. Understanding the neuroendocrinology characteristic of PPD has proven to be particularly challenging given the erratic changes to the brain and biological systems during pregnancy and postpartum. A review of exploratory studies in PPD has observed that women with PPD have more dramatic changes in
HPA axis activity, however, the directionality of specific hormone increases or decreases remain mixed. Hormones that have been studied include
estrogen,
progesterone,
thyroid hormone,
testosterone,
corticotropin releasing hormone, endorphins, and
cortisol. Aberrant steroid hormone-dependent regulation of neuronal calcium influx via extracellular matrix proteins and membrane receptors involved in responding to the cell's microenvironment might be important in conferring biological risk. The use of synthetic
oxytocin, a birth-inducing drug, has been linked to increased rates of postpartum depression and anxiety.
Estradiol, which helps the uterus thicken and grow, is thought to contribute to the development of PPD. Profound
lifestyle changes that are brought about by caring for the
infant are also frequently hypothesized to cause PPD. However, little evidence supports this hypothesis. Mothers who have had several previous children without experiencing PPD can nonetheless experience it with their latest child. Despite the biological and psychosocial changes that may accompany pregnancy and the postpartum period, most women are not diagnosed with PPD. Many mothers are unable to get the rest they need to fully recover from giving birth. Sleep deprivation can lead to physical discomfort and exhaustion, which can contribute to the symptoms of postpartum depression.
Risk factors While the causes of PPD are not understood, several factors have been suggested to increase the risk. These risks can be broken down into two categories, biological and psychosocial:
Biological • Administration of labor-inducing medication synthetic
oxytocin • Genetic history of PPD • Hormone irregularities The risk factors for postpartum depression can be broken down into two categories as listed above, biological and psychosocial. Certain biological risk factors include the administration of oxytocin to induce labor. Chronic illnesses such as diabetes, or Addison's disease, as well as issues with
hypothalamic-pituitary-adrenal dysregulation (which controls hormonal responses), A correlation between postpartum thyroiditis and postpartum depression has been proposed but remains controversial. There may also be a link between postpartum depression and anti-thyroid antibodies.
Psychosocial • Prenatal depression or anxiety • A personal or family history of depression • Stressful life events experienced during pregnancy •
Postpartum blues • Childhood trauma • Previous stillbirth or
miscarriage • A lack of strong emotional support from spouse, partner, family, or friends • Infant temperament problems/
colic • Maternal age, family food insecurity, and violence against women The psychosocial risk factors for postpartum depression include severe life events, some forms of chronic strain, relationship quality, and support from partner and mother. There is a need for more research regarding the link between psychosocial risk factors and postpartum depression. Some psychosocial risk factors can be linked to the
social determinants of health. Rates of PPD have been shown to decrease as income increases. Women with fewer resources may be more likely to have an unintended or unwanted pregnancy, increasing the risk of PPD. Women with fewer resources may also include single mothers of low income. Single mothers of low income may have more limited access to resources while transitioning into motherhood. These women already have fewer spending options, and having a child may spread those options even further. Low-income women are frequently trapped in a cycle of poverty, unable to advance, affecting their ability to access and receive quality healthcare to diagnose and treat postpartum depression.
Sexual orientation has also been studied as a risk factor for PPD. In a 2007 study conducted by Ross and colleagues, lesbian and bisexual mothers were tested for PPD and then compared with a heterosexual sample group. It was found that lesbian and bisexual biological mothers had significantly higher Edinburgh Postnatal Depression Scale scores than the heterosexual women in the sample. Lesbian women have a higher risk of depression because they are more likely to have been treated for depression and to have attempted or contemplated suicide than heterosexual women. Different risk variables linked to postpartum depression (PPD) among Arabic women emphasize regional influences. Risk factors that have been identified include the gender of the infant and
polygamy. Studies have also shown a correlation between postpartum depression in mothers living within areas of conflicts, crises, and wars in the
Middle East. The phrase ‘integration of care’ describes an approach in healthcare in which multiple providers from differing specialties collaborate to manage a patient’s care. Integrating care in postpartum patients showed similar rates of depression in comparison to the non-integrated healthcare approach. The same study mentions it also may not impact rates of substance abuse. In addition, for women receiving breastfeeding support, the location where education was given also did not have a noticeable impact on depression or anxiety. About one-third of women throughout the world will experience physical or sexual violence at some point in their lives. Violence against women occurs in conflict, post-conflict, and non-conflict areas. The research reviewed only looked at violence experienced by women from male perpetrators. Studies from the
Middle East suggest that individuals who have experienced family violence are 2.5 times more likely to develop PPD. Further, violence against women was defined as "any act of gender-based violence that results in, or is likely to result in, physical, sexual, or psychological harm or suffering to women". Psychological and cultural factors associated with increased incidence of postpartum depression include family history of depression, stressful life events during early puberty or pregnancy, anxiety or depression during pregnancy, and low social support. Violence against women is a chronic stressor, so depression may occur when someone is no longer able to respond to the violence. ==Diagnosis==