The cause of<unk>  is unknown. Hormonal and physical changes, personal and family history of<unk> , and the stress of caring for a new baby all may contribute to the development of<unk> . Evidence suggests that hormonal changes may play a role. Understanding the neuroendocrinology characteristic of<unk>  has proven to be particularly challenging given the erratic changes to the brain and biological systems during pregnancy and<unk> . A review of exploratory studies in<unk>  have observed that women with<unk> , have more dramatic changes in HPA axis activity, however directionality of specific hormone increases or decreases remain mixed. Hormones which have been studied include estrogen, progesterone, thyroid hormone, testosterone, corticotropin releasing hormone, endorphins, and cortisol. Estrogen and progesterone levels drop back to pre-pregnancy levels within 24 hours of giving birth, and that sudden change may cause it. 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<unk>  and anxiety. Fathers, who are not undergoing profound hormonal changes, can also have<unk> . The cause may be distinct in males. Profound lifestyle changes that are brought about by caring for the infant are also frequently hypothesized to cause<unk> . However, little evidence supports this hypothesis. Mothers who have had several previous children without suffering<unk>  can nonetheless suffer it with their latest child. Despite the biological and psychosocial changes that may accompany pregnancy and the<unk>  period, most women are not diagnosed with<unk> . 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<unk> . Risk factors While the causes of<unk>  are not understood, a number of factors have been suggested to increase the risk. These risks can be broken down into two categories, biological and psychosocial: Biological Risk Factors * Administration of labor-inducing medication synthetic oxytocin * Chronic illnesses caused by neuroendocrine irregularities * Genetic history of<unk>  * Hormone irregularities * Inflammatory illnesses (irritable bowel syndrome, fibromyalgia) * Formula feeding rather than breast feeding * Cigarette smoking The risk factors for<unk>  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 hypothalamic-pituitary-adrenal dysregulation (which controls hormonal responses), inflammatory processes like asthma or celiac disease, and genetic vulnerabilities such as a family history of<unk>  or<unk> . Chronic illnesses caused by neuroendocrine irregularities including irritable bowl syndrome and fibromyalgia typically put individuals at risk for further health complications. However, it has been found that these diseases do not increase risk for<unk> , these factors are known to correlate with<unk> . This correlation does not mean these factors are causal. Cigarette smoking has been known to have additive effects. Some studies have found a link between<unk>  and low levels of DHA (an omega-3 fatty acid) in the mother. A correlation between<unk>  thyroiditis and<unk>  has been proposed but remains controversial. There may also be a link between<unk>  and anti-thyroid antibodies. Psychosocial Risk Factors * Prenatal<unk>  or anxiety * A personal or family history of<unk>  * Moderate to severe premenstrual symptoms * Stressful life events experienced during pregnancy *<unk>  blues * Birth-related psychological trauma * Birth-related physical trauma * History of sexual abuse * Childhood trauma * Previous stillbirth or miscarriage * Formula-feeding rather than breast-feeding * Low self-esteem * Childcare or life stress * Low social support * Poor marital relationship or single marital status * Low socioeconomic status * A lack of strong emotional support from spouse, partner, family, or friends * Infant temperament problems/colic * Unplanned/unwanted pregnancy * Breastfeeding difficulties * Maternal age, family food insecurity and violence against women The psychosocial risk factors for<unk>  include severe life events, some forms of chronic strain, relationship quality, and support from partner and mother. There is a need for more research in regard to the link between psychosocial risk factors and<unk> . Some psychosocial risk factors can be linked to the social determinants of health. Women with fewer resources indicate a higher level of<unk>  and stress than those women with more resources, such as financial. Rates of<unk>  have been shown to decrease as income increases. Women with fewer resources may be more likely to have an unintended or unwanted pregnancy, increasing risk of<unk> . 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. Studies have also shown a correlation between a mother's race and<unk> . African American mothers have been shown to have the highest risk of<unk>  at 25%, while Asian mothers had the lowest at 11.5%, after controlling for social factors such as age, income, education, marital status, and baby's health. The<unk>  rates for First Nations, Caucasian and Hispanic women fell in between. Migration away from a cultural community of support can be a factor in<unk> . Traditional cultures around the world prioritize organized support during<unk>  care to ensure the mother's mental and physical health, wellbeing, and recovery. One of the strongest predictors of paternal<unk>  is having a partner who has<unk> , with fathers developing<unk>  50% of the time when their female partner has<unk> . Sexual orientation has also been studied as a risk factor for<unk> . In a 2007 study conducted by Ross and colleagues, lesbian and bisexual mothers were tested for<unk>  and then compared with a heterosexual sample group. It was found that lesbian and bisexual biological mothers had significantly higher Edinburgh Postnatal<unk>  Scale scores than did the heterosexual women in the sample. These higher rates of<unk>  in lesbian/bisexual mothers may reflect less social support, particularly from their families of origin and additional stress due to homophobic discrimination in society. There is a call to integrate both a consideration of biological and psychosocial risk factors for<unk>  when treating and researching the illness. Violence A meta-analysis reviewing research on the association of violence and<unk>  showed that violence against women increases the incidence of<unk> . 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. 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<unk>  include family history of<unk> , stressful life events during early puberty or pregnancy, anxiety or<unk>  during pregnancy, and low social support. Violence against women is a chronic stressor, so<unk>  may occur when someone is no longer able to respond to the violence.
Postpartum depression
Postpartum blues
Postpartum disorder
Dysphoric milk ejection reflex
Postpartum psychosis
Premenstrual syndrome
Post-adoption depression syndrome
Premenstrual dysphoric disorder