Researchers in China enrolled 291 mother–child pairs to examine the relationship between maternal zinc status in the third trimester and infant weight and length at birth, six months, and 12 months, aiming to clarify the role of maternal zinc levels in early childhood growth and development.
Results revealed a “dynamic association between maternal zinc status and infant physical development during the first year of life,” the researchers wrote.
“The critical role of maternal zinc nutrition in shaping the early growth trajectory of children is worth paying attention to,” they added.
Maternal zinc in pregnancy essential for fetal growth
Maternal nutrition, including trace elements, directly supports fetal growth through placental nutrient transfer.
Zinc requirements increase during pregnancy to meet the needs of rapid fetal growth. The mineral supports enzymatic activity, cellular structure and biological regulation, including DNA synthesis, cell growth, immune function and hormone regulation.
Previous research has linked maternal zinc deficiency to adverse outcomes such as preterm birth, low birth weight and restricted fetal growth.
However, evidence of the association between maternal zinc levels and newborn physical development remains inconsistent, according to the authors of the new study. They note that some studies report lower maternal zinc levels in cases of low birth weight or small-for-gestational-age infants, while others find no association with infant weight or length.
Maternal zinc levels during pregnancy boost early infant weight and length
The researchers conducted the study at the Fourth Affiliated Hospital of China Medical University between January 2019 and August 2024, enrolling pregnant women over 18 years old who delivered single, full-term infants (37–42 weeks).
They collected maternal blood samples at delivery after at least 8 hours of fasting to measure zinc levels, and participants completed questionnaires that recorded maternal age, ethnicity, weight before pregnancy and weight during late pregnancy.
During telephone follow-ups at six and 12 months, researchers collected infant feeding patterns and growth data from community health examinations.
The researchers also calculated pre-pregnancy body mass index and pregnancy weight gain, and calculated weight and length growth rates for infants.
Results showed that infants born to mothers with sufficient zinc had slightly higher birth weights than those born to zinc-deficient mothers (nearly 30% of participants). However, the difference did not reach statistical significance and maternal zinc status was not associated with birth length.
At six months of age, infants of zinc-sufficient mothers weighed more and were longer than infants of zinc-deficient mothers. However, maternal zinc status showed no significant association with infant weight or length at 12 months. The authors noted that this could be due to factors which would reduce the long-term impact of zinc exposure during pregnancy, such as genetic factors, complementary feeding and environmental influences.
They also found that maternal zinc status was linked to faster weight and length gain in early infancy, an effect they hypothesized may occur because zinc influences hormone regulation, supports immune function and provides infants with higher zinc reserves after birth.
They concluded that maternal zinc sufficiency was associated with higher birth weight-for-age scores, and that maternal zinc status also showed significant positive associations with both weight-for-age and length-for-age scores at six months.
Furthermore, faster early growth did not increase the risk of obesity at six months. The infants of zinc-sufficient mothers did not show higher weight-for-length scores, suggesting that improved growth did not lead to unhealthy weight gain.
The researchers concluded that adequate zinc nutrition during pregnancy supports early infant growth, particularly in the first six months of life, but noted that larger, multi-center studies with longer follow-up and more comprehensive nutritional and developmental measures are needed to confirm these results and clarify the long-term effects of maternal zinc on child health.
Source:Frontiers in Nutrition; doi: 10.3389/fnut.2026.1762341; “Association between maternal zinc status and the physical development of infants aged 0–12 months: a cohort study in Northeast China.” Authors: J. Dong et al.
