Yi Ying Ong, Nicholas Beng Hui Ng and Yung Seng Lee

Imagine two babies born at full term. Baby A had a normal growth rate in the womb but is born naturally small, while Baby B is born small after their growth in the womb slowed down. Baby B’s “fetal growth deceleration” may have been caused by placental issues or other conditions limiting the baby’s nutrient and oxygen supply, potentially affecting their brain development. Research studies have often lumped Baby A and Baby B together under the categories of “low birthweight” or “small for gestational age”, but these conditions are different from slowed fetal growth. As such, it remains unclear how fetal growth deceleration affects children’s cognitive abilities. 

Now, let’s look at what happens after birth — some believe that if Baby B’s growth catches up, it might compensate for the earlier growth problems and support better brain development. But is this true?