The Role of Nutrition in Fetal Development and Beyond

Development from fetus to child to adult depends on maternal nutrition and health long before conception.

By Alexa Morales

A baby’s early years of life can look different in every family. One thing, however, remains the same: their baby is vulnerable. Malleable and fragile. Delicate. Easily damaged if not cared for appropriately. 

The first thousand days of an infant’s life are crucial, but parents often aren’t adequately prepared. Oftentimes, only mothers hear about eating a balanced diet during pregnancy and post-partum or about the importance of breastfeeding and the timely introduction of complementary foods to an infant’s diet. As such, public health officials and health providers must emphasize the importance of nutrition from preconception through the first thousand days among the larger population, as this period is critical to an infant’s development. 

The first thousand days begins from conception and ends at the child’s second birthday. Many, however, would argue that that this crucial window is longer than a thousand days, instead starting at before conception. The choices parents-to-be make even before their baby is conceived can shape a baby’s cognitive development, nutrition, and environment, setting the foundations for their lifelong health.  

“This is a time period of enormous potential, but also enormous vulnerability,” says Melissa Young, PhD, associate professor of global health at Emory University. The slightest healthier changes in nutrition can make a big difference. “Improving nutrition during this narrow window of time can have a huge impact on improving health for a whole lifetime,” she adds.

Young and fellow researchers from Emory University explored the connection between maternal preconception nutrition and infant growth, including the risk of stunting, in a recent study in the Public Library of Science. They found that women who were shorter and underweight at preconception were at an increased risk of having a stunted child by age two, using data from a micronutrient supplementation trial in Vietnam. 

Young and her colleagues propose their findings are intertwined with the Developmental Origins of Health and Disease hypothesis. Often referred to as Barker’s Hypothesis, this idea suggests that a fetus’s environment, as well as overall health while during gestation, can affect its risk of developing chronic diseases later in life. This happens through a mechanism called maternal programming, the transfer of nutrients across the placenta. 

“The placenta indicates to the fetus the quality of the external environment,” says Aryeh Stein, PhD, associate professor of global health at Emory University. In other words, a baby’s health starts in the intrauterine environment, and thus, can be influenced by the mother’s health and nutrition even before pregnancy.

This system is highly efficient in connecting the mother’s nutrition to the fetus. The fetus obtains nutrients and grows appropriately if the mother herself is properly nourished. On the other hand, the fetus will make certain adaptations to allow it to develop in a tougher environment if the mother is undernourished.  

“The problem arises when the fetus gets it wrong. In other words, the fetus has indications that the outside environment is short on nutrients, but in fact, there is an over-abundance of nutrition,” says Stein.  

Stein and a team of researchers analyzed this in a longitudinal study by examining the intergenerational effects of improving nutrition during pregnancy and early childhood in a small community in Guatemala. In the initial study, called the INCAP study, researchers performed a nutrition supplementation trial in four rural villages between 1969 and 1977. Since then, researchers have collected data on maternal and child dietary intakes, illness, growth and development over five decades. 

“We are interested in studying how they have developed, how tall they have become, and if they have developed chronic diseases,” Stein says.

Stein and Emory researchers found that stunting during early childhood among girls was a predictor for their own infant’s size. Additionally, younger age at first pregnancy — less than 20 years of age — was also associated with an increased risk of stunting.  These findings not only reaffirm the importance of nutritional improvements starting at preconception, but they also provide new insights into how a person’s overall health in adulthood starts early on through developmental plasticity. 

“Developmental plasticity suggests that, at some point in the fetal and early childhood development process, the child is set up in a developmental trajectory that, from that point on, is fixed,” Stein says. Even if this trajectory is not fixed, Stein notes, it is difficult for it to move into a different direction. 

Furthermore, there are other health implications related to nutrition from preconception through the first thousand days, such as cognitive development. Researchers examined the relationship between early-life stature, preschool cognitive development, schooling level attained, and cognitive functioning during adulthood in a study published in the Lancet. They used data from four birth cohorts from Brazil, Guatemala, the Philippines, and South Africa. 

The researchers found a strong association between adult IQ and early childhood cognition. They also found associations between early-life stature, cognitive development, and schooling outcomes, although these varied across the four cohorts. These findings suggest that nutritional improvements, along with physical and mental stimuli, can produce better cognitive outcomes in the future.

“Investing in nutrition, improving nutritional status, improving health, and reducing illness can all have effects on improving school performance and learning potential later on,” says Young. 

A child’s lifelong health is deeply influenced by nutrition during this critical window from preconception through the first thousand days of life, shaping their growth, cognitive development, and chronic disease risk. Therefore. it is important to continue investing in maternal and child health from an early stage, as this can impact not only individual health, but also the health of future generations.