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Postnatal depression is a form of clinical depression which can affect women, and less frequently men, after childbirth. It is widely considered to be treatable. Studies report prevalence rates from 5% to 25%, but methodological differences among the studies make the actual prevalence rate unclear.
'Baby' or maternity blues are a mild and transitory form of 'moodiness' suffered by up to 80% of postnatal women. Fathers also suffer from postnatal depression. Symptoms typically last from a few hours to several days, and include tearfulness, irritability, hypochondriasis, sleeplessness, impairment of concentration, isolation and headache. The maternity blues are not considered a postpartum depressive disorder.
While not all causes of PND are known, several factors have been identified. Beck (2001) has conducted a meta-analysis of predictors of PPD. She found that the following 13 factors were significant predictors of PPD (effect size in parentheses -- larger values indicate larger effects):
- Prenatal depression, i.e., during pregnancy (.44 to .46)
- Low self esteem (.45 to.47)
- Childcare stress (.45 to .46)
- Prenatal anxiety (.41 to .45)
- Life stress (.38 to .40)
- Low social support (.36 to .41)
- Poor marital relationship (.38 to .39)
- History of previous depression (.38 to.39)
- Infant temperament problems/colic (.33 to .34)
- Maternity blues (.25 to .31)
- Single parent (.21 to .35)
- Low socioeconomic status (.19 to .22)
- Unplanned/unwanted pregnancy (.14 to .17)
Other factors identified in people suffering from postnatal depression are:
- history of genetic mental illnesses
- substance abuse
- former childbirth issues
These factors are known to correlate with PPD. That means that, for example, high levels of prenatal depression are associated with high levels of postnatal depression, and low levels of prenatal depression are associated with low levels of postnatal depression. But this does not mean the prenatal depression causes postnatal depression -- they might both be caused by some third factor. In contrast, some factors, such as lack of social support, almost certainly cause postnatal depression. (The causal role of lack of social support in PPD is strongly suggested by several studies, including O'Hara 1985, Field et al. 1985; and Gotlib et al. 1991.)
Although profound hormonal changes after childbirth are often claimed to cause PND, there is little evidence that variation in pregnancy hormone levels is correlated with variation in PPD levels: Studies that have examined pregnancy hormone levels and PND have usually failed to find a relationship (see Harris 1994; O'Hara 1995). Further, fathers, who are not undergoing profound hormonal changes, suffer PND at relatively high rates (e.g., Goodman 2004). Finally, all mothers experience these hormonal changes, yet only about 10-15% suffer PPD. This does not mean, however, that hormones do not play a role in PPD. For example, found that, in women with a history of PPD , a hormone treatment simulating pregnancy and parturition caused these women to suffer mood symptoms. The same treatment, however, did not cause mood symptoms in women with no history of PPD. One interpretation of these results is that there is a subgroup of women who are vulnerable to hormone changes during pregnancy. Another interpretation is that simulating a pregnancy will trigger PND in women who are vulnerable to PPD for any of the reasons indicated by Beck's meta-analysis (summarized above).
Women most commonly experience depression during their primary reproductive years (25 to 45), so they are especially vulnerable to developing depression during pregnancy and after childbirth.
Profound lifestyle changes brought about by caring for the infant are also frequently claimed to cause PPD, but, again, there is little evidence for this hypothesis. Mothers who have had several previous children without suffering PPD can nonetheless suffer it with their latest child (Nielsen Forman et al. 2000). Plus, most women experience profound lifestyle changes with their first pregnancy, yet most do not suffer PPD.
In severe cases, postnatal psychosis (also known as puerperal psychosis) can develop, characterized by hallucinations and delusions. This happens in about 0.1 - 0.2% of all women after having given birth. In some cases, postpartum psychosis can develop independent of postpartum depression.
Sometimes a pre-existing mental illness can be brought to the forefront through a postnatal depression. Postpartum depression can be hereditary. Women with severe premenstrual syndrome most commonly suffer from postpartum depression.
Evolutionary psychological hypothesis
Evolutionary approaches to parental care (e.g., Trivers 1972) suggest that parents (human and non-human) will not automatically invest in all offspring, and will reduce or eliminate investment in an offspring when the costs outweigh the benefits, that is, when the offspring is "unaffordable." Reduced care, abandonment, and killing of offspring have been documented in a wide range of species. In many bird species, for example, both pre- and post-hatching abandonment of broods is common (Ackerman et al. 2003; Cezilly 1993; Gendron and Clark 2000).
Human infants require an extraordinary degree of parental care. Lack of support from fathers and/or other family member will increase the costs borne by mothers, whereas infant health problems will reduce the evolutionary benefits to be gained (Hagen 1999). If ancestral mothers did not receive enough support from fathers or other family members, they may not have been able to afford raising the new infant without harming any existing children, or damaging their own health (nursing depletes mothers' nutritional stores, placing the health of poorly nourished women in jeopardy).
For mothers suffering inadequate social support or other costly and stressful circumstances, negative emotions directed towards a new infant could serve an important evolved function by causing the mother to reduce her investment in an unaffordable infant, thereby reducing her costs. Numerous studies support the correlation between postpartum depression and lack of social support or other childcare stressors (Beck 2001; Hagen 1999).
Mothers with postnatal depression can unconsciously exhibit fewer positive emotions and more negative emotions toward their children, are less responsive and less sensitive to infant cues, less emotionally available, have a less successful maternal role attainment, and have infants that are less securely attached; and in more extreme cases, some women may have thoughts of harming their children (Beck 1995, 1996b; Cohn et al. 1990, 1991; Field et al. 1985; Fowles 1996; Hoffman and Drotar 1991; Jennings et al. 1999; Murray 1991; Murray and Cooper 1996). In other words, most mothers with PPD are suffering some kind of cost, like inadequate social support, and consequently are mothering less.
On this view, mothers with PND do not have a mental illness, but instead cannot afford to take care of the new infant without more social support, more resources, etc. Treatment should therefore focus on helping mothers get what they need. (See Hagen 1999 and Hagen and Barrett, n.d.)
Effects on the parent-infant relationship
Postnatal depression may lead mothers to be inconsistent with childcare. Women diagnosed with post- partum depression often focus more on the negative events of childcare, tending to make themselves have poor coping strategies (Murray).
There are four groups of coping methods, each divided into a different style of coping subgroups. Avoidance coping is one of the most common strategies used (Murray). It consists of denial and behavioral disengagement subgroups (for example, an avoidant mother might not respond to her baby crying). This strategy however, does not resolve any problems and ends up negatively impacting the mother’s mood, similarly of the other coping strategies used (Honey).
Four Coping Strategies:
- Avoidance Coping: denial, behavioral disengagement
- Problem-Focused Coping: active coping, planning, positive reframing
- Support Seeking Coping: emotional support, instrumental support
- Venting Coping: venting, self-blame
Mothers who may be using avoidance coping and don’t respond to their infants needs may make the infant feel insecure. According to Edhborg’s article on long-term impacts, insecurity can lead to infant stress and infant avoidance, where the infant may become so subdued that it will not interact with the mother or any other adult. This is a concern because months two through six in an infant’s life are very important; it is in these months that the infant develops some interaction and cognitive skills. Parent-infant interaction is most essential during this time because it builds the connection not only with the mother, but others as well (Long-term). It is also the time of most risk for the child because of a possible increased onset of depression in the mother (Long-term). The lack of interaction can lead to difficulties in parent-infant communication and result in poorer infant performance (Murray).
Edhborg and some colleagues did a study on mother-child attachment by using forty-five randomly selected mother-child pairs. These pairs were chosen using an Edinburgh Postnatal Depression Scale (EDPS) form, measuring postpartum depression in the community. 326 women returned the form and of the 326, twenty-four scoring above twelve were recruited and twenty-one women scoring less than nine were recruited. Scoring above twelve is considered potentially depressed while those scoring less than nine are considered to have no form of depression. The forty-five mother-child pairs were then taken and videotaped, in their homes, for five minutes in three different situations. Mother and child were first put in a room with a standard set of toys, to represent a control play. In the second situation, the mother and child were allowed to play freely in an average toy room. In the third situation, the mother was asked to leave the room as if she had to check on something, like she would regularly do in their home environment, and then return.
Senior Psychologists then scored the interaction between mother and child. The first two taped situations were scored on a five point scale; 1 (being the area of most concern) to 5 (being an area of strength). In the third situation, the attachment behavior was put into three groups based on how the child reacted to the mothers return.
Three classified groups:
- Secure and Joyful Attachment: consists of child greeting mother with joy and being comforted by her presence.
- Secure Attachment but Restricted in Expressed Enjoyment and Pleasure: consists of the child acknowledging the mother, but showing little joy than would normally be expected.
- Insecure Attachment: consists of child showing signs of avoidance and resistance. In the form of resistance the child would go to the mother, but then pull away and often repeat this action.
Analysis showed only one difference between the groups. In the free play situation, children with high EPDS scores showed less interest in playing with their mothers and exploring on their own than the children with low EPDS scores. The mothers too only showed one difference. Those with a high EDPS score showed little maternal emotional availability to the child.
Following the results, Edhborg performed a cluster analysis, keeping interest on the different interaction styles. Some children did show signs of depression, but when comparing the children it was found that there is no significance with the EPDS scores and the interaction styles. The study did find, however, that children of high EPDS scorers were less involved in the free play situation than the children of low EPDS scorers, showing that children of high EPDS are more likely to be insecure.
When performing the structured task from the first situation it showed that the mothers with high EPDS were “aware of their unavailability for the child in the early postpartum period and thus tried harder… to help their children succeed in the task” (Edhborg). This overreaction proves that too much interaction can cause a negative mood in the child and a continuing difficulty in mother-child communication.
Attachment issues have been shown to be a problem in older children, also. As a result of being exposed to the depression symptoms, as an infant, older children may have impaired cognitive and socio-emotional developments. The lack of attachment can also cause troubles in the interaction with others and personal independence (Long-term). Children with these issues have a higher risk of being diagnosed with depression later in life as well (Honey).
Prevention and screening
Early identification and intervention improves long term prognoses for most women. Some success with preemptive treatment has been found as well. A major part of prevention is being informed about the risk factors, and the medical community can play a key role in identifying and treating postpartum depression. Women should be screened by their physician to determine their risk for acquiring postpartum depression.
The United States Preventive Services Task Force (USPSTF) recommends screening for depression. A systematic review conducted by the USPSTF has found adequate evidence that screening for depression, when combined with an effective support system for positive screens, improves clinical outcomes and is of moderate net benefit. Results from a systematic review of 6 trials, screening pregnant and postpartum women 18 years of age or older, showed a 18%-59% relative reduction and a 2.1%-9.1% absolute reduction in the risk of depression at follow-up (3-5 months) compared with usual care.
The American Academy of Pediatricians (AAP) recommends screening at well-child visits at 1, 2, 4 and 6 months.
Although there is no clear consensus as to which scale is recommended for screening postpartum depression, the two most widely utilized screening scales are the Patient Health Questionnaire (PHQ-9) and the Edinburgh Postnatal Depression Scale (EPDS). Although PHQ-9 and EPDS measure depression, they capture two distinct aspects of postnatal depression. The PHQ-9 assesses common somatic symptoms during pregnancy and in the immediate postnatal period, while the EPDS detects depressive symptoms comorbid with anxiety. Multiple studies have concluded that PHQ-9 and EPDS may be applied with equal confidence in screening for major depressive episodes in postpartum women.
Currently, Alberta is the only province in Canada with universal PND screening which has been in place since 2003. The PPD screening is carried out by Public Health nurses in conjunction with the baby's immunization schedule. Also, proper exercise and nutrition appears to play a role in preventing postpartum, and general, depression.
Nutrition / Prevention
Nutrition: Nutrition has shown itself to be a factor in the condition known as postpartum depression. Many scientists in the medical community have begun to publish their findings in the area. Some aspects of what role nutrition plays in a woman’s chance of suffering from this condition have become quite controversial while others have been embraced as useful aids to help combat suffering from postpartum depression. One area of the nutrition factor that is shrouded in a great deal of controversy and is fiercely debated by both sides of the issue is the use of aspartame and other sugar supplements during the course of a pregnancy. Many independent studies claim that aspartame is a carcinogen and that when ingested produces large amounts of phenylalanine in the body which can lead to birth defects such as mental retardation. This is due to the fact that the phenylalanine can disrupt the connections being made in the fetuses developing brain. Aspartame has also been linked to causing abnormal serotonin production in the brain. Due to these findings some doctors caution pregnant woman not to use aspartame, based on the concern that low serotonin levels in the brain could greatly increase the risk of suffering from the effects of postpartum depression. Despite the findings of these independent studies done on aspartame the FDA, Searle / Monsanto (the company that birthed the chemical), and the Food and Beverage Association of America vigorously defend the safety of their product and claim that the findings against aspartame should be viewed as “urban myths.” One factor in regards to the diet of pregnant women that most doctors agree upon is the increased need for omega-3 fatty acids. It is recommended that pregnant women ingest at least 1,000 mg (1 gram) of omega-3 oils every day. This amount of oil can be obtained through any of these examples: 2 teaspoons of walnut oil, 2 to 3 oz. of cooked salmon, or 1/3 teaspoons of flaxseed oil. Pregnant woman choosing to eat fish as a way obtain their necessary amount of omega-3’s should limit their intake to 12 oz a week. This is due to the mercury levels found in fish that could be potentially harmful to a mother’s unborn child or to infants being reared on breast milk containing high amounts of the toxic element. Along with omega-3’s, protein also plays an important role in the diet of a pregnant woman. When the body breaks down protein it allows the brain to produce the neurotransmitter serotonin, which helps to relive anxiety. It is recommend that nursing mothers ingest 71 grams of protein per day while non-nursing mothers only need 46. Protein can be found in a wide variety of foods. Some examples along with their protein content are as follows: 3 oz of most meat products contain about 25 gm, 3 large eggs will hold 19 gm, and 3 oz of Swiss cheese will have about 15 gm.
Hydration: One of the most important roles in any diet (especially for pregnant and nursing mothers) is that of hydration. Drinking enough liquid is a key part in combating postpartum depression. Studies have shown that dehydration can cause feelings of fatigue and anxiety. If a woman already suffering from postpartum depression failed to keep herself properly hydrated, the chances of her condition worsening would be almost certain. It is recommend that pregnant women make sure to consume ten 8oz glasses of water every day. Mothers who are nursing are strongly urged to drink a tall glass of water, milk, or juice before sitting down to breast-feed their child. Another aspect of liquid diet concerning postpartum women is the consumption of alcohol and caffeine. Despite the feelings of light euphoria alcohol may seem to induce it is a depressant. It is recommend that postpartum women greatly limit their alcohol intake until they feel emotionally stable and physically recovered from the strains of giving birth. Caffeine consumption is also a concern in the diets of pregnant and postpartum women. While it is common practice for someone to use caffeine as a way to raise ones alertness, when consumed in large amounts it has been shown to cause a variety of side effects such as: restlessness, anxiety, and headaches. All these conditions can be very detrimental to pregnant and postpartum women. It is recommended that pregnant and nursing mothers consume no more than 300 mg of caffeine a day. It is also recommended that if one decides to stop using caffeine they should wean them selves off the drug slowly. This is due to the concern that by eliminating caffeine abruptly (rather than in small steps) it may induce intense headaches, feelings of irritation, and lethargy.
Vitamins: While vitamins cannot be relied upon to solely provide an individual with all the nutrition they need, vitamins can do a great deal to help combat postpartum depression. It is highly recommend that postpartum women take a daily prenatal supplement to aid them in meeting all their nutritional needs. When choosing a prenatal vitamin one should look for a supplement containing high amounts of iron and vitamins A, C, and E. Warning: While vitamin A is essential to normal fetal development, high amounts are teratogenic, ie. cause birth defects. Even twice the daily recommended amount can cause severe birth defects, while certain acne medicines contain enough amounts to be teratogenic after a single use.   
Appetite: It is extremely important for pregnant and postpartum women to maintain a healthy appetite. A proper calorie intake is a key part in keeping one feeling healthy and positive both during the pregnancy and in the first few months after the birth. If a woman finds herself with a strong lack of appetite she should consult her physician. This may be a sign of postpartum depression and therefore should be brought to the attention of ones doctor. Cortisol is produced as a response to stress and cannot be converted into serotonin. the intake of any substance, including caffeine may produce an overload of cortisol, which in turn limits the production of serotonin, causing a higher risk of postpartum depression. amino acid tryptophan and vitamin B6 is essential in the process of building serotonin.
Treatments for PPD are largely the same as for clinical depression in general. If the cause of PPD can be identified, treatment should be aimed at the root cause of the problem.
Women need to be taken seriously when symptoms occur. [That is, she must take her symptoms seriously enough to tell her significant other, or a close friend, or her medical practitioner. Also, THEY must take her symptoms seriously as well.] Generally a combination of psychotherapy and medication can reduce symptoms. The ideal treatment plan includes:
- Medical evaluation to rule out physiological problems
- Psychiatric evaluation
- Possible medication
- Support group
- Home visit
- Healthy diet
- Consistent/ healthy sleep patterns
It is critical that women being treated for postpartum depression prolong the treatment even after symptoms subside, because if treatment is ceased prematurely, symptoms can reoccur.
Postnatal psychosis or PNP, is a mental illness, which involves a complete break with reality. Although correctly termed as a postnatal stress disorder or postpartum depressive reaction, Postnatal psychosis is different from post-partum depression. The majority of PNP occurs within the first two weeks after childbirth with a classic 10-14 day meltdown, likely caused by the radical hormonal changes combined with neurotransmitter overactivity. When correctly diagnosed at the earliest signs and immediately treated with anti-psychotic medication, the illness is recoverable within a few weeks. If undiagnosed, even for just a few days, it can take the woman months to recover. In cases of PNP, the sufferer is often unaware that she is unwell.
Psychosis can also take place in combination with an underlying psychiatric disorder, such as bipolar affective disorder, schizophrenia, or undiagnosed depression. In some women, a part-partum psychosis is the only psychotic episode they will ever experience, but, for others, it is just the first indication of a psychiatric disorder. Only 1 to 2 women per 1,000 births develop post-partum psychosis. It is a rare condition, and often treatable. However, much media coverage of post-partum depression has focused on psychosis, especially following the Andrea Yates case. Whilst postpartum/puerperal psychosis is a serious psychiatric illness, the risks of a mother suffering this illness harming her baby are low: infanticide rates are estimated at 4%, and suicide rates in postpartum/puerperal psychosis are estimated at 5%.
PNP is also known as "postnatal stress disorder", because the patients are notably under emotional stress and exhibits unusual behavioral patterns not seen before their pregnancy or post-partum event. Symptoms associated with PP are memory lapses (periods of confusion or similar to amnesia), random or uncontrollable "anxiety" attacks and unintelligible speech or communication.
Andrea Yates case
After the National Organization for Women (NOW) insisted that Andrea Yates had postnatal depression, the Individualist Feminists of Ifeminist.com pointed out that postnatal depression is quite common and that most sufferers do not murder their children. In fact, Yates suffered from postnatal psychosis. After Ifeminist.com pointed out that this stigmatized a large number of mothers and made them less likely to seek professional help, NOW removed their claims from their official website. Some believe that Yates' fundamentalist church bears some responsibility for the murder, as the church allegedly urged her to ignore her psychiatrist's orders. Yates methodically drowned her children in a bathtub in her Clear Lake City, Houston, Texas house on June 20, 2001.
Melanie Stokes died of Postnatal Psychosis several months after her daughter's birth in February 2001. Ms. Stokes had a textbook perfect pregnancy; her husband was a physician; she was a successful business woman.
Melanie's mother started a website to raise awareness about Postpartum Psychosis: http://www.melaniesbattle.org/index.html Her work also led to the introduction of the Melanie Stokes Postpartum Depression and Research and Care Act (HR 20) in 2001: http://www.melaniesbattle.org/legislation.html The Act was reintroduced to Congress in 2007 as HR 846: http://www.ppdil.org/billalert.htm
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