Stress during pregnancy may result in having babies who have low birth weight, a new study has found.
Researchers from the University of California Los Angeles (UCLA) found that even before a woman becomes pregnant, her biological makeup - particularly the levels of stress hormone cortisol - may signal such outcome.
Maternal Cortisol Levels
Cortisol is a hormone that regulates bodily processes in times of stress. Normally, cortisol levels increase by two to four times during pregnancy. However, when cortisol increases far beyond that range, both immediate and long-term impacts may occur.
Immediate effects of increased cortisol include having decreased blood flow to the fetus. This then leads to the baby being deprived of oxygen and necessary nutrients.
"We found that the same cortisol pattern that has been linked with chronic stress is associated with delivering a baby that weighs less at birth," says study lead author Christine Guardino.
Co-lead author Chris Dunkel Schetter adds that a baby whose mother has very elevated cortisol levels may also have problems with dealing with stress later in life.
Health Before Pregnancy
Although past studies have shown that stress hormones play a huge role in the growth and development of babies, this new study is the first to provide evidence that the stress physiology or cortisol patterns before a mother's pregnancy are also essential in determining a baby's birth weight. This then suggests that the events in the life of a woman, as well as her overall health, matter.
Such implication signifies that women who plan to get pregnant must consider the effects of their daily stresses once they conceive and start planning for a healthy pregnancy.
"Improving pre-conception health can profoundly improve our overall health," says Schetter. This means that women should manage ongoing stresses, treat depression if present and obtain support from family members. All the factors needed to have a good pregnancy and healthy life as a mother starts before getting pregnant.
The Study
The research involved 142 women who provided saliva samples and became pregnant during the Community Child Health Network study.
The researchers found that the mothers' stresses came from finances, relationships within the family and neighborhood issues. Major life events such as death in the family, racism and interpersonal violence were also noted.
The authors determined the levels of stress by analyzing the participants' body mass index, blood pressure and cortisol levels in the saliva. They also conducted interviews among mothers and fathers in their places of residence.
The team is now performing a follow-up study on the newborn babies, who are now between 3 to 5 years old.
The study was published online in the journal Health Psychology.
