Let’s help reduce stress during pregnancy
STUDIES conducted in both animals and humans have shown that stress during pregnancy is bad for fetal brain development, which can result in school failure, behavioral problems, physical abnormality, language delay (failure of a child to meet language developmental milestones for his or her age), and reduced cognition. The studies also suggest that the quality of prenatal environment influences child brain development.
In the first prospective study of the consequences of prenatal maternal anxiety, researchers reported less gray matter volume in some parts of the brain of 6-9-year-old children, whose mothers experienced high levels of prenatal stress anxiety (PSA) early in gestation. According to them, MRI (magnetic resonance imaging) has indicated this particular effect on the child’s brain especially among children of women highly stressed during the early second trimester of pregnancy.
And some of the affected brain regions are known to support different cognitive functions, among them, the prefrontal cortex (“thinking part”), the premotor cortex (movement), the medial temporal lobe (long-term memory), the lateral temporal cortex as well as the cerebellum.
The prefrontal cortex is involved in executive functions such as reasoning, planning, attention, working memory, and some aspects of language. Structures in the medial temporal lobe, including areas connected to the hippocampus (memory center), are also affected. Brain parts that help in learning languages include the inferior frontal gyrus, the middle temporal gyrus, and the parahippocampal gyrus.
Is maternal bereavement due to a loss of a close relative during pregnancy associated with the risk of birth defect in offspring?
Of the 1,771,663 children in the study, researchers found 35,118 (2 percent) born to mothers who experienced bereavement during the period between a year before pregnancy and the end of the first trimester. The children were from several 1978-2008 national registers in Denmark.
Of these groups, 3,040 children were found with cleft—968 with cleft lip, 1,203 with cleft lip and palate, and 869 with cleft palate only.
Experimental animal models have shown that another prominent outcome of prenatal stress is increased fear and anxiety in the offspring. Few prospective human studies have studied the result of prenatal stress during preadolescence of the affected children.
One hundred seventy-eight mother-child pairs were studied. Maternal psychological distress (general anxiety, perceived stress, depression and pregnancy-specific anxiety) and biological stress signals were looked into at 19, 25 and 31 gestational weeks. Anxiety was evaluated in children when they reached 6-9 years of age, using the Child Behavior Checklist.
Analyses revealed that prenatal exposure to high maternal cortisol, depression, perceived stress and pregnancy-specific anxiety was associated with increased anxiety in children, who face an increased risk of developing anxiety during the preadolescent period. The study showed prenatal risk factors associated with child mental health problems; but at the same time it raised the possibility that reducing maternal stress during the prenatal period will have long-term benefits in children.
Millions of children all over the world have language delay. The delay is commonly attributed to an older sibling or one of the parents who were themselves late in talking; or to prematurity. Now, with new findings on cognitive research, stress during pregnancy is recognized as a cause of language delay.
In January 1998 an ice storm occurred in Maine (where I was practicing) and in the Canadian province of Quebec. The storm caused massive power blackouts for up to 40 days in areas populated by 3 million people. In June 1998, researchers from Douglas Hospital Research Center, led by Dr. David Laplante, sent a group of pregnant women questionnaires about their stress due to the ice storm.
After five and half years, the children of those who suffered from the ice storm were tested with the Wechsler Preschool and Primary Scale of Intelligence-Revised and Peabody Picture Vocabulary Test. The mothers were asked again to complete assessments of recent life events and psychological functioning.
The research team of Laplante found that children exposed in utero to high levels of stress had lower full scale IQs, verbal IQs, and language abilities compared to children exposed to low or moderate levels of prenatal maternal stress. The study further showed that prenatal exposure to a moderately severe natural disaster is associated with lower cognitive and language abilities among children up to five and half years of age.
With the new studies showing the bad effects of stress during pregnancy and the arrival of effective social networking, and with support from national TV and newspapers, we should start a campaign to educate everyone, including parents, physicians, nurses, hospital administrators, policymakers, so there will be a conscious collective effort to give fetuses positive experiences. Thus we may be able to reduce school failure and behavioral problems among children and help enhance our children’s mental capabilities so that they can better compete in the global arena.
Dr. Leonardo L. Leonidas ([email protected]) retired in 2008 as assistant clinical professor in pediatrics from Boston’s Tufts University School of Medicine, where he was recognized with a Distinguished Career in Teaching Award in 2009. He is a 1968 graduate of the University of the Philippines College of Medicine and now spends some of his time in the province of Aklan.
