What factor is most closely related to fetal growth during early pregnancy?

Maternal nutrition is crucial for fetal growth during early pregnancy as it directly impacts the quality and availability of the nutrients required for the developing fetus. During the first trimester, the foundational structures and organs are forming, and adequate maternal nutrition ensures that the fetus receives sufficient energy, protein, vitamins, and minerals essential for optimal development. Nutrient deficiencies or poor maternal nutrition can lead to issues such as low fetal weight or developmental delays, highlighting the importance of proper dietary intake for the health of both mother and baby.

While maternal activity level, stress, and age certainly play roles in pregnancy health, they do not have the same direct influence on fetal nutrient provision and growth in the early stages as nutrition does. Proper maternal nutrition is essential for fostering a healthy environment for fetal growth and is the primary factor that ensures the developing fetus has the necessary resources for critical early growth.