Why the conversation on early childhood development needs to start before birth

Published on
August 19, 2021

For some time now, early childhood experts have acknowledged that the first few years of a child’s life are critical for neurological development, and that growing up in a stressful environment can actually change the structure of the budding brain.

Now researchers are increasingly finding that the human brain is shaped — quite literally, in some instances — by external forces while it is still in utero.

“We really need to understand that development begins before birth, and parenting begins before birth,” said Catherine Monk, a professor of medical psychology in the OB-GYN and psychiatry departments of Columbia University Irving Medical Center. “That can be a focus in terms of prenatal and preconception attention for parents-to-be and giving them the support that they need.”

For instance, a recent study from researchers at the Children’s National Hospital in Washington, D.C., found that low socioeconomic status in pregnant women was associated with decreased brain tissue and altered development in their fetuses, putting the babies at risk for a variety of neurological and psychiatric disorders later in life.

Vidya Rajagopalan, a USC Keck School of Medicine researcher who was not part of the project, called the March study published in JAMA Network Open “groundbreaking.” She said it builds on previous landmark research that has found huge gaps in the number of words that children in poor households hear compared to their richer counterparts, affecting their vocabularies and learning abilities.

“We've already had compelling evidence that growing up in poverty really compromises a person's potential,” said Monk, who was also not involved with the study. “But this suggests that risk starts to develop in utero, and really supports the idea of early intervention and support for families on the transition to parenthood, when they're becoming families, as the woman is pregnant.”

She said a likely mechanism for the changes in the developing fetus is the stress-hormone cortisol crossing into the placenta and impacting the formation of nerve cells and their connecting synapses. But she also noted that the growing brain has tremendous plasticity, so “there’s always tons of opportunity for change. These are risk factors, and they’re subtle.”

The researchers analyzed 144 healthy women with uncomplicated pregnancies between 24 and 40 weeks of gestation. The women filled out questionnaires about their occupations and educational attainment, and had MRI scans of their fetuses to measure brain volume indicators like white matter, cerebellum and brainstem. 

“Higher parental education, occupation and SES (socioeconomic status) scores were associated with significantly increased volume in key regions of the fetal brain, including regions involved in relaying communication between brain regions, sensory perception and balance control,” noted study author Catherine Limperopoulos, chief and director of the Developing Brain Institute at Children’s National Hospital.

“We've already had compelling evidence that growing up in poverty really compromises a person's potential. But this suggests that risk starts to develop in utero, and really supports the idea of early intervention and support for families on the transition to parenthood, when they're becoming families, as the woman is pregnant.”

She said she hopes the research further highlights the need for enhanced early childhood education and interventions, as well as the importance of stress-reduction techniques like meditation and yoga both before and — with a doctor’s approval — during pregnancy.

Another study published early this year found a relationship between prenatal maternal stress and toddler sleep problems.

And Rajagopalan, the USC researcher, is involved in a multisite study that will try to determine whether giving mental health treatment to pregnant women whose babies have congenital heart defects positively impacts fetal brain development.

“The long-term goal of the project is to see if we can improve outcomes in these babies by helping with one layer of the complications,” she said.

That research could help shed more light on the role of maternal stress in these fetal brain changes, said Jessica Wisnowski, an assistant professor of research radiology and pediatrics with the USC Keck School of Medicine. But there are many factors — lack of nutrition, sleep issues, racism and discrimination — that may contribute. Which of these often overlapping variables have the biggest impact, and how, is something that science will have to determine in the years ahead, she noted.

Wisnowski pointed out that data from animal studies shows that the trajectory of the fetal brain may start before the pregnancy begins. Researchers have been finding that the neurological effects of chronic stress may be inheritable, possibly through a process called epigenetics, or the way behaviors and environment can alter gene function. “The beginning of the beginning may actually be generations before the fetus is conceived,” Wisnowski said.

Rajagopalan said prenatal screenings could one day test for things like cortisol levels and nutritional deficiencies. However, Wisnowski said there would first need to be accompanying robust social policies to support women, so they’re not just labeled as “high-stress mommies.”

Wisnowski said this emerging line of research is already telling us that early childhood cognitive health programs like First 5 California need to broaden their scope to before birth. She said that while the young brain has the capacity to bounce back, it also has inherent vulnerabilities because of the fact that it is still developing. So the earlier interventions take place, the better. 

“Hopefully we can have commercials that are not just, ‘Hey, First 5 California,’ but, ‘Hey, pregnant moms and, hey, families with pregnant moms, here’s what we can do to better support that child’s development. Like, do the dishes so Mom can go to bed an hour early,’” she said. 

Finding ways to bolster mothers, especially during pregnancy, could lead to lifelong benefits for their children. “How can we as a society better support moms in all sorts of ways like to make sure that at their jobs they’re getting adequate periods of rest, adequate time for nutrition and all those sorts of things?” Wisnowski asked.

“What this research is starting to tell us is that if we wait to think about intervening on child development after birth, we miss the fact that all this is beginning before birth.”