Developmental Biology: Pregnancy Stress Hormones May Shape When a Child’s First Teeth Appear, Study Finds
A new study from the University of Washington is providing novel insight into how a child's environment in the womb can influence their development long after birth. Researchers found a significant link between the level of stress hormones a mother experiences during pregnancy and the timing of her child’s first tooth eruption.
The findings suggest that maternal stress, particularly during the third trimester, might play a previously unrecognized role in the biological mechanism that determines dental development, adding another layer to the complex interplay between maternal and child health.
The Link Between Cortisol and Tooth Eruption
The study focused on cortisol, the primary stress hormone, which is known to cross the placenta and affect fetal development. Researchers analyzed cortisol levels and compared them to the age at which the children’s primary (baby) teeth began to erupt.
Delayed Eruption: The research indicated that higher maternal cortisol levels were associated with a later age of first tooth eruption in the child.
The Critical Window: The strongest association was found with cortisol levels measured during the third trimester of pregnancy, suggesting this period is crucial for the development and mineralization processes that precede tooth eruption.
Biological Mechanism: The proposed mechanism suggests that cortisol may interfere with the cells responsible for laying down the mineral structure of teeth (ameloblasts and odontoblasts) or affect the timing of the processes that trigger the teeth to emerge from the gums.
This research aligns with other studies showing that maternal factors, including genetics, nutrition, and environmental stress, can be "etched" into a child's developing tissues.
Implications for Early Childhood Dental Health
The timing of tooth eruption is a significant marker of a child’s overall development and has been linked to future risk of dental issues. While delayed eruption can be a benign variation, understanding the factors that control this timing is crucial:
Monitoring Development: Knowledge of this link can help pediatric dentists and healthcare providers better understand variations in early dental development.
Maternal Health: The findings underscore the importance of maternal well-being and stress management during pregnancy, not just for general fetal development but specifically for the child's oral structures.
The researchers note that this is an observational study and further research is needed to fully clarify the biological pathway and clinical significance of this link. However, it establishes maternal stress as an important developmental consideration in pediatric dentistry.
Original Article Details
Original Title: Pregnancy stress hormones may shape when a child’s first teeth appear, study finds
Source: Oral Health Group (Content via University of Washington News)
Publication Date: November 17, 2025