Effects of Cortisol and Stressful Birth on Children

There has been some concern that stressful birth can lead to aggression in children later in life. Is this caused by cortisol levels during or at birth? What are possible effects of cortisol and stressful birth on children?

A recent study published in BJOG, an International Journal of Obstetrics and Gynecology, showed a link between childhood aggression and the delivery method used at birth. What researchers found was an increase in cortisol levels in blood samples from the umbilical cords in babies who had a stressful birth. Stressful birth was determined to be those that were vaginally assisted with the use of forceps or vacuum. Lowest cortisol levels were found in babies delivered by c-section.

Cortisol is a hormone released in the body in response to stress. It's actually beneficial in the short term by increasing brain function and energy levels in stressful situations. Cortisol is also important in metabolism and in how the body uses protein, carbohydrates and fat stores in the body. However, these short-term benefits are only recognized in adults.

Though beneficial in the short-term, long-term effects of high cortisol levels can effect blood sugar levels and affect the immune system and inflammation.

Long-term exposure to high cortisol levels in children might actually affect development in many systems of the body. Studies of children exposed to long-term maternal stress and continued early exposure to cortisol can lead to early emotional disorders such as depression and anxiety. It may also cause behavioral problems and aggression.

But what about short-term effects of cortisol due to stressful birth on children? The short-term effects of cortisol are supposed to be helpful to the body in stressful situations. What is considered short-term for adults may be too long for a newborn exposed to high levels of cortisol.

Also, the amount of cortisol in a newborn's system may be higher in relation to that of an adult in stressful situations. Until the umbilical cord is cut, the infant may receive high amounts of cortisol from the mother as well during a stressful birth. As a baby's system is not fully developed, in addition to the higher amounts of cortisol, the metabolism of this stress hormone may be much slower and harder to get rid of.

Studies are conflicting on the effects of cortisol and stressful birth on children. Some claim that a stressful birth is enough to cause later aggression and behavior problems in children. However, other studies show that if exposure to stress is lower during the early childhood years, there is no continuing effect from stressful birth. It is agreed that increased cortisol levels from continued exposure to stress, especially maternal stress, is a factor in determining a school-aged child's emotional and behavioral actions.

However, since studies show the lowest cortisol levels in babies born by c-section and the increased rate of c-sections worldwide, it would seem behavioral and emotional problems would be reduced in children. Yet more and more children are being diagnosed with these issues. More research will need to be done to find if there are any long-term effects of cortisol and stressful birth on children.

SOURCES:

H-T li, et al.; Caesarean delivery on maternal request and childhood psychopathology: a retrospective cohort study in China; BJOG: An International Journal of Obstetrics and Gynecology

Marilyn J Essex, et al.; Maternal stress beginning in infancy may sensitize children to later stress exposure: effects on cortisol and behavior; Biological Psychiatry