Study: Maternal distress can set the stage for childhood behavioral issues

12/04/2023 / By Olivia Cook

Stress that the mother experiences during pregnancy can set the stage for her child’s behavioral issues in the future, according to a study.

Growing evidence notes that stress and distress – which occurs when stress is prolonged, severe or both – during pregnancy is linked to offspring risk for externalizing behavior outcomes, such as reactive/aggressive behaviors, hyperactivity and impulsivity, among others.

A new study published by the American Psychological Association in the journal APA PsycNET suggested that psychological stress and distress during the pregnancy period uniquely increases the odds of “children developing and exhibiting aggressive, disinhibited and impulsive behaviors.” Researchers noted that while effects may be relatively small, they may persist across developmental periods from early childhood through adolescence.

In a separate study published in the British Journal of Psychiatry, researchers from the Royal College of Psychiatrists (RCP) in London found that mothers-to-be who experience even moderate stress during their pregnancy are nearly four times more likely to have offspring who develop a personality disorder.

They also implied that women who are severely stressed during the duration of their pregnancy are, in some cases, nearly 10 times more likely to have children who are at risk of developing a personality disorder by age 30 – when compared with those whose mothers experience little or no stress during the period between conception and birth.

The impact of prenatal stress on a child’s development can carry over to the family environment and parent-child relationships – both of which could increase the likelihood, suggested the authors. (Related: Healthy habits and mental well-being: Natural ways to beat depression.)

How the study was done

The RCP researchers gathered data from a total of 3,626 individuals in Helsinki, Finland. The participants were born between July 1, 1975, and June 30, 1976, and had mothers who completed regular health and well-being assessments during their pregnancies.

Each month, the mothers answered a question on mental stress since their last doctor’s visit – no stress, some stress, or notable stress.

What the study found

After 30 years, using data obtained through the Finnish Hospital Discharge Register and the Finnish National Population (when the sample individuals would have been around 30 years old), the researchers found 40 of the 3,626 samples had a diagnosed personality disorder – after accounting for variables, including maternal smoking during pregnancy, parental psychiatric history and subjective feelings of depression before, during and after pregnancy.

“It highlighted the importance of providing mental health and stress support to pregnant women and families during the antenatal and postnatal period,” said Dr. Ross Brannigan, lead author from the Royal College of Surgeons in Ireland.

“One in 20 people in the United Kingdom have been diagnosed with a personality disorder, which can lead to psychosocial impairment, increased rates of suicide, functional impairment and increased long-term use of health services,” according to the RCP’s Mental Health Information.

Limitations of the study

RCP Perinatal Faculty Chair Dr. Trudi Seneviratne noted that the study did not account for important factors that may affect pre- and postnatal stress and child development, such as family financial situation, parenting style or sexual trauma, among others, “which we know contribute to stress in pregnant women.”

Prenatal stress on child behavioral outcomes

The “Encyclopedia on early childhood development” includes many independent studies that have shown that if a mother is stressed, anxious or depressed while pregnant, her child is at increased risk of having a range of problems, including attention deficit (ADHD), behavioral or conduct disorders, emotional problems and impaired cognitive development.

Here are two situations that show how stress during pregnancy can handicap children from before they are even born and produce lasting undesirable changes in both the mother and her child.

First, when a pregnant woman feels stress, the “fight or flight response” is initiated and her adrenal glands inject a group of stress hormones called catecholamines that consist of adrenaline and nor-adrenaline into her circulation.

Because her body is being prepared for fight or flight, her blood is diverted from the internal organs, such as the stomach and the intestines, to the large muscles of the legs – diminishing normal blood supply to the uterus.

For a pregnant woman, this means that her baby will receive less blood and therefore, less oxygen and nutrients. The consequences can be terrible if this persists.

This also means that her parasympathetic nervous system, which controls her body’s ability to relax, is inhibited – leading to wakefulness and difficulty in digestion or absorption of nutrients from food.

Second, if a pregnant woman experiences acute stress, such as the death of a loved one or loss of a job, or is a single mother worried about how she will support the child she is carrying, her amygdala (a major processing center for emotions) will override signals from her hippocampus (which plays a major role in learning and memory). This also “stokes the fires in the adrenals” so they keep producing the stress hormones cortisone (derived from the metabolism of cortisol), adrenaline and noradrenaline.

In either case, a pregnant woman’s body is flooded with loads of stress hormones – and also the fetus growing within her.

Stress hormones and the baby’s developing brain

Cortisol is an essential hormone that plays many important roles in almost every organ and tissue in the body, including the body’s stress response, but at the same time, too much of it can almost be poison.

Research has shown that abnormally high and prolonged cortisone concentrations in utero have many harmful effects on the developing fetus, particularly in the construction of the brain.

It can lead to cell migrations to the wrong destinations – resulting in abnormal neural circuits and interference with the baby’s internal states, such as sleep and digestion.

In chronic stress, a large concentration of stress hormones will destroy vital dendrites, neurons, synapses and so on. Stress also decreases the production of oxytocin (the so-called love hormone) and increases the production of vasopressin (a hormone that supports aggressive behavior).

Continuous secretion and circulation of glucocorticoids, particularly cortisol, eventually leads to a reduction of dopamine – decreasing activity in the brain’s pleasure pathways, reducing norepinephrine that can result in a lack of alertness and motivation and a lowering of serotonin that can greatly reduce feelings of happiness and well-being.

Because of all these factors, babies who are exposed to their mother’s prenatal stress will have a very strong tendency to develop a personality disorder.

Head over to WomensHealth.news for more stories on women’s health and healthy pregnancies.

Watch the following video to learn how child personality disorders are linked to prenatal stress.

This video is from the Daily Videos channel on Brighteon.com.