Schizophrenia Prevention - Risk Reduction Approaches

Pregnancy and Schizophrenia - The Importance of Low Stress During Pregnancy for Healthy Brain Development

Make Extra Effort to Maintain Low Levels of Physical, Social and Emotional Stress & Anxiety (worry, fear and perfectionism) During Pregnancy.

Its important for all family members and extended family to make extra effort to create an environment of low stress for the woman during pregnancy to allow healthy brain development of the child. Reseach suggests that high levels of social and emotional stress, or even chronic moderate stress, can have negative impacts on the fetus' brain during pregnancy. The mother and the uterine environment she creates have a major contribution to many aspects of fetal development and a number of key brain development steps that occur during that time impact a child throughout its life. The exact consequences of hormonal variations in the womb on our intelligence, personality, and emotional and physical health is beginning to be understood. There's also an emerging understanding of a new area of science called fetal programming, which says that the health effects of our life in the womb may be not be felt until decades after we're born, and in ways that are more powerful than previously imagined.

When we feel stressed, we normally experience a range of effects -- our pupils dilate, our blood pressure and heart rate rise, and our emotions heighten. What we don't see are the internal effects. A message reaches the pituitary gland at the base of the brain and is relayed to the adrenal glands, where the stress hormone cortisol is secreted into our bloodstream. The placenta inactivates most of the mother's cortisol before it reaches the fetus, but some of it gets into the fetal bloodstream.

The mother's cortisol also can cause the placenta to release corticotrophin-releasing hormone (CRH), which goes directly to the fetus. This causes the fetus to secrete its own cortisol, which stimulates the placenta to secrete even more CRH, creating for the fetus a self-perpetuating stress-hormone loop.

Janet DiPietro, an associate professor of maternal and child health at the Johns Hopkins School of Public Health and one of the few fetal-behavior specialists in the US, says that research tells us that the fetus is bathed in hormones generated by what the mother is feeling, and these hormones affect the underlying fetal brain environment that shapes its personality and temperament, she says. "Temperament has to be formed this way. It wouldn't make any sense for it not to. A woman who is going up and down all day with stress hormones and changes in heart rate and blood pressure causes her fetus to get a very uneven distribution of oxygen. This is not good for its ultimate homeostatic well-being."

This happens because maternal stress triggers the secretion of not only cortisol but another stress hormone, adrenaline. Adrenaline and adrenaline-like stress hormones can cause uterine contractions that disturb the fetus and can constrict blood vessels that diminish blood flow -- and oxygen -- to the fetus. Lack of oxygen to the fetus brain is well known to be harmful to the child's brain during pregnancy and has been identified as an important factor in increasing risk for schizophrenia. Maternal factors such a stress and stress hormones have been shown to play a significant role in pregnancy outcomes related to premature birth - another factor that is associated with underweight babies and higher risk of schizophrenia.

A study of pregnant women during the Quebec ice storm also concluded that stress during pregnancy significantly stalls children's brain development, making them less intelligent, more anxious and more prone to bad behaviour. The children of pressured pregnant mothers even had mismatched fingerprints, a sure sign of impairment during the development of the fetal brain. Billed as the first scientific look at the impact of stress on unborn babies, the project found toddlers whose mothers were under the most strain during the storm had IQs almost 20 points lower on average than the offspring of lower-stressed women. Additional research studies have further suggested that lower IQs are associated with higher risk for psychosis and schizophrenia.

In another study that demonstrates how stress impacts brain development, a research program completed in 2001 found that women who have had a major stressful event - death of a spouse, job loss, or a long-distance move - midway through their pregnancy may have a greater chance of having an autistic child than do their unstressed counterparts, say researchers at The Ohio State University Medical Center.

And, after yet another recent study (2006), researchers have suggested that women who work more than 32 hours a week in stressful jobs risk the health of their unborn child. Babies born to these women have been found to be five ounces lighter than the average birth weight - the same as those of pregnant smokers. (low birthweight is very bad for babies; where the woman is of normal size, a low birth weight baby suggests the developing child experienced poor nutrition, low oxygen, high stress, or other problems in the womb. Moreover low birthweight is associated with greatly increased risk for many physical and mental disorders including low IQ, and significantly increased risk of psychiatric disorders).

The results provide fresh evidence of the effect of stress on a developing baby and has led the man in charge of the research to call on pregnant women to work no more than 24 hours a week. The study, involving 7,000 women, and conducted by the Amsterdam Born Children and their Development research group, also found that mothers suffering from stress are more likely to have babies that cry excessively. Other research has shown that certain jobs that are higher in stress cause depression and anxiety in people at a high rate (see: Stressful job link to depression)

And it revealed that mothers who worked long hours have an increased risk of developing pre-eclampsia, a serious complication of pregnancy caused by a defect in the placenta that restricts blood flow to the baby. Prof Gouke Bonsel, who headed the study, said: "Women with high stress jobs would do better to work no more than 24 hours per week from the beginning of pregnancy.''

Dr. Janet DiPietro believes maternal stress can "affect the set point for stress responsiveness" in the developing baby. In other words, children born to mothers who have especially strong reactions to stress may themselves grow up to be highly sensitive to stress and react negatively when exposed to stress.

Although we respond to emotional stress differently because it is filtered through our individual personality and temperament, we don't always know how we're reacting physically. In her research, DiPietro finds that when women are asked to describe how they feel when put to stress tests, their answers often don't correspond to their measured stress levels. A number of women who said they didn't feel especially stressed were in fact highly stressed, according to the monitors, and some who said they felt stressed had relatively low measured stress levels.

While research definitely suggests that high levels of stress is bad for the fetus during pregnancy, and research also suggests that babies that have the genes associated with mental illness are more sensitive to stress, moderate levels of occasional maternal psychological stress during pregnancy may actually enhance fetal maturation for some babies, according to researchers from the Johns Hopkins University and the National Institute of Child Health and Human Development, in a study is published in the May/June 2006 edition of the journal Child Development.

The authors found one exception to their study results: the children of women who regarded their pregnancy as more negative than positive showed slightly poorer emotional control and attention capacity.

DiPietro believes pessimism is a major generator of stress and stress hormones. She says an expectant mother's stress burden is greatly eased when she views her pregnancy optimistically and chooses to focus on its positive aspects and doesn't worry much. (for more information on how to develop this positive attitude, we highly recommend the books "Feeling Good" and "When Panic Attacks: The New Anxiety Therapy That Can Change Your Life by Dr. David Burns, and Mindset by Dr. Carol Dweck.)

DiPietro finds that highly pressured mothers-to-be tend to have more active fetuses -- and more irritable infants. "The most stressed are working pregnant women," says DiPietro. "These days, women tend to work up to the day they deliver, even though the implications for pregnancy aren't entirely clear yet. That's our cultural norm, but I think it's insane."

Some researchers agree that working can be an enormous stress, but emphasize that pregnancy hormones help to buffer both mother and fetus. Individual reactions to stress also matter. "The pregnant woman who chooses to work is a different woman already from the one who chooses not to work,"

She's also different from the woman who has no choice but to work. DiPietro's studies show that the fetuses of poor women are distinct neurobehaviorally-less active, with a less variable heart rate-- from the fetuses of middle-class women. Yet "poor women rate themselves as less stressed than do working middle-class women," she notes. DiPietro suspects that inadequate nutrition and exposure to pollutants may significantly affect the fetuses of poor women.

Stress, diet, and toxins may combine to have a harmful effect on intelligence. A recent study by biostatistician Bernie Devlin, Ph.D., of the University of Pittsburgh, suggests that genes may have less impact on IQ than previously thought and that the environment of the womb may account for much more. "Our old notion of nature influencing the fetus before birth and nurture after birth needs an update," DiPietro insists. "There is an pre-birth environment, too, that is provided by the mother."

Additional insights into the impact of stress on a developing baby came in a study designed to find out why African-American babies are twice as likely to have low birth weight than white babies. On average, African-American babies weigh about one-half to two-thirds of a pound less than white babies and significantly less than Hispanic, Native American, and American-born Asian babies.

Because birth weight is vital to the overall health of a baby, this weight difference is significant and may be one reason why African-American babies have double the infant-mortality rate of white babies.

Because the weight difference has remained so consistent over the years, genes were widely assumed to be the cause. Dr. James Collins, medical director of the neonatal intensive-care unit at Children's Memorial Hospital in Chicago, wasn't so sure. He devised a study by examining the birth records of three groups of newborns: babies born to US-born African-American women; white women; and African-born black women living in the US.

He looked at the records of nearly 90,000 babies and compared their birth weights. In a study published in the New England Journal of Medicine, he effectively debunked the genetic theory of birth weight.

Both white and African-born mothers gave birth to babies of similar birth weights, but the American-born African-American mothers had babies of lower birth weight. If genes were the controlling factor, the birth weights of babies born to the African-American and African-born black women should have been equivalent.

So what is the cause of lower-birth-weight African-American babies? Collins doesn't think the major factor is diet; he thinks it's the mother's stress.

"It may not just be the stress the expectant mother experiences," Collins says. "It may go back to her mother or her mother's mother. A grandmother may give birth to a low-birth-weight baby, who in turn gives birth to a low-birth-weight child. It may be an intergenerational effect we're seeing."

Collins says the mother's stress could be related to poverty, racism, and the climate of fear in the neighborhoods in which many of them live. The stress they feel probably is also layered with feelings of pessimism and hopelessness. White women subjected to similar emotional stresses also have lower-birth-weight babies.

Extreme emotional stress is thought to put developing babies at risk for a variety of physical disorders. Fetal researcher Peter Nathanielsz notes that many years ago the French discovered that physical and emotional stress led to terrible outcomes for the babies of young laundry mistresses. "The French finally figured out these women worked long and hard and stood on their feet all day," he says. "As a result, their blood pooled in their feet and their fetuses didn't get enough blood."

Animal studies have found that high cortisol levels can weaken cells and interfere with fetal brain development, resulting in a wide range of brain and behavior problems for the offspring. A Finnish study found children born to mothers who suffered the emotional shock of losing their husband had a bigger risk of developing serious mental disorders (for example, studies suggest that the risk of the child developing schizophrenia is increased by 600%). The researchers cautioned that the shock didn't directly cause the illnesses; rather, it appears to be a factor for offspring with an underlying biological or genetic susceptibility. Nonetheless, the study points out how important a mother's state of mind may be in the development of her unborn child.

The study also underscores the notion that in life, including prenatal life, timing can be everything. The affected children were born to mothers who learned of their husbands' deaths in the second trimester. Mothers who received the jolting news in the first or third trimesters did not have children with a higher risk of mental disorders.

While most women in North America don't live under conditions of extreme stress. Nonetheless, DiPietro thinks that as a society we are putting too much stress on pregnant women.

"For thousands of years, some cultures, like the Chinese, have had strict prohibitions against exposing pregnant women to stress," she says. "One woman from China told me that her parents did not tell her pregnant sister that their grandmother had died. They waited until after she delivered to tell her."

Not so in the United States, she says. "Our society has gone crazy with our policy to work right up until the time you have a child," DiPietro adds. "In our study we found women tend to work until the day they go into labor. Then after a few weeks at home, they return to work. It's absurd. They don't catch up on their sleep for years. They are too mentally and physically depleted. This is just so foolish, and now it's become the norm."

Peter Nathanielsz says wakefulness and rest patterns are important in pregnancy, because animal studies indicate that continual disruption of maternal and fetal circadian rhythms may be harmful. "A pregnant woman who gets up at 3 in the morning to go to work or take one of their kids to a hockey rink puts a lot of stress on her and the fetus she carries," he adds.

Expectant mothers are also cautioned about exercising beyond their established limits or in conditions such as hot weather or high altitudes that they're not accustomed to. Both can stress the fetus by depriving it of needed oxygen.

"We have to understand our own biology during pregnancy," Dr. Nathanielsz says. "We ignore it at our peril."

Because temperament and personality are critical to stress reaction, there's some disagreement as to how much a woman can reduce emotional stress and what kind of impact that will have on her unborn child. "We can say stress is bad," says DiPietro, "but that doesn't tell women what to do about it."

For that reason, other than encouraging pregnant women to think positive thoughts and to try to avoid placing stress on themselves, there's been little concrete advice. (for more information on how to "think positive thoughts" - see
the software/web sites listed at the end of the recommended reading list below).

Dr. Nathanielsz proposes a simple prescription: "The best thing pregnant women can do is lie down and relax as much as they can during the day," he says. "This will ease their stress, bring maximum blood and oxygen to the fetus, and enhance the health of their pregnancy."

Its also very valuable for women who are pregnant to have close and frequent interactions with their close friends and family members that make them feel good and who they can discuss issues and challenges with. Isolation from friends and family during pregnancy is a type of stress - especially if the husband/father is not frequently available for support, or if there are significant issues with the relationship between husband and wife.

Husbands should be extra emotionally supportive during their wife's pregnancy, and make extra effort to make things easy for pregnant woman so as to make their pregnancy as low stress as possible.

Recommended Reading:

Pregnancy Anxiety, Depression and Stress Results in Sensitive Children, Increased Risk for Mental Health Problems

Stress Harms Baby's Brain While in Womb

Maternal stress during pregnancy is associated with a higher risk of schizophrenia for child

Stress Impact on Mother and Child during pregnancy

Pregnancy stress 'passed to baby' (BBC)

Child and Teen Brains Very Sensitive to Stress, Likely a Key Factor in Mental Illness

Chronic Mild Stress During Pregnancy May Increase Risk of Brain Disorders in Child

Treat depression during pregnancy (if not earlier), researchers urge (New Scientist)

Stress Hormones and Schizophrenia

Anxiety during pregnancy affects child behavior

Schizophrenia and Stress

Pregnancy and the Mind

Stressful event kills brain cells

Higher Stress and Anxiety During Pregnancy Means Smaller Babies

Stress in pregnancy hits offspring's emotional brain (New Scientist)

Stress; brain damage also found in other mammals (chickens) (Economist)

Noise Activates Our Stress Hormones

Excessive Startle Response in Schizophrenia


How to Lower Stress, Anxiety, Worry and Depression Before Pregnancy:

Recommended Internet Software: MoodGym - For Prevention of Depression (Free) For this to be most effective, you must work through all the modules of the software.

Some very good "for-pay" internet software therapy for the treatment of depression and anxiety can be found here (Depression Relief) and here (Anxiety / Stress/ Worry Relief). Read more about the software here: Beating the Blues.

Web psychotherapy 'just as good' as face to face therapy (BBC) - this story suggests that some web therapy may be as helpful as therapy with a psychologist - so it seems like a good idea to try web therapy (as in the above links).

Recommended Books: These books should be available from your local libraries.

Feeling Good and The Feeling Good Handbook - By Dr. David Burns

When Panic Attacks: The New Anxiety Therapy That Can Change Your Life by Dr. David Burns

Work on developing a positive perspective on life's challenges with a "growth mindset". Read the following book: Mindset: The New Psychology of Success By Dr. Carol Dweck, Stanford University. Learn more here: The Effort Effect (Stanford University Alumni Magazine)

Seek out a qualified psychologist or psychiatrist if you are having difficulty dealing with any stress, anxiety and worry, sadness or depression. Its always better to get help from the psychologist sooner rather than later - and quick treatment is especially important when a woman is pregnant.

Related readings:

SSRI antidepressants do not pose major birth defect risk































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