Divine Aleru is an accomplished biochemist and researcher with a specialized background in environmental toxicology, focusing on the impacts of heavy metals on human health. With deep-rooted expertise in microbiome signatures analysis, Divine seamlessly blends rigorous scientific training with her passion for deciphering the intricate relationships between environmental exposures and the human microbiome. Her career is distinguished by a commitment to advancing integrative health interventions, leveraging cutting-edge microbiome research to illuminate how toxic metals shape biological systems. Driven by curiosity and innovation, Divine is dedicated to translating complex environmental findings into actionable insights that improve individual and public health outcomes. 
Divine Aleru is an accomplished biochemist and researcher with a specialized background in environmental toxicology, focusing on the impacts of heavy metals on human health. With deep-rooted expertise in microbiome signatures analysis, Divine seamlessly blends rigorous scientific training with her passion for deciphering the intricate relationships between environmental exposures and the human microbiome. Her career is distinguished by a commitment to advancing integrative health interventions, leveraging cutting-edge microbiome research to illuminate how toxic metals shape biological systems. Driven by curiosity and innovation, Divine is dedicated to translating complex environmental findings into actionable insights that improve individual and public health outcomes. What was studied?
This study conducted a systematic review and meta-analysis to assess the impact of maternal mercury exposure during pregnancy on adverse birth outcomes (ABO), such as low birth weight (LBW), preterm birth (PTB), and small-for-gestational-age (SGA) births. The analysis synthesized observational studies published between 2004 and 2024 to evaluate these associations, particularly focusing on mercury exposure’s role in birth weight and anthropometric measures.
Who was studied?
The study involved a diverse array of pregnant women from various global regions, including populations exposed to mercury through environmental, occupational, and dietary sources. The studies included varied in geographic location and methods of mercury exposure measurement, such as blood, hair, and urine mercury levels. The pregnant women studied ranged in socioeconomic backgrounds and included those from both industrialized and developing countries, providing a broad spectrum of data on mercury exposure during pregnancy.
Most important findings
The review found a positive association between maternal mercury exposure (MHE) and the risk of low birth weight (LBW) (OR = 1.079). However, no significant association was found between MHE and preterm birth (PTB) or small-for-gestational-age (SGA) outcomes. The meta-analysis also indicated that each 10-fold increase in MHE was linked to abnormal birth anthropometrics, including reduced birth length and head circumference. The association was particularly notable in late pregnancy, highlighting that this period might be a sensitive window for the impacts of mercury exposure on fetal development.
Key implications
The findings underscore the importance of regulating mercury exposure during pregnancy, especially as it relates to low birth weight, a key risk factor for infant morbidity and mortality. The results suggest that mercury exposure during late pregnancy poses significant risks for adverse birth outcomes, particularly in terms of birth weight and anthropometric measurements. Given the limited association with PTB and SGA, further studies are needed to pinpoint the precise timing and thresholds of mercury exposure that lead to these outcomes. These findings are important for the HTMC program, as they advocate for stricter mercury exposure limits, especially for populations of pregnant women, and emphasize the need for accurate exposure assessments using consistent biomarkers.
Citation
Pan, K., Xu, J., Li, F., Yu, H., & Yu, J. (2025). The association between mercury exposure during pregnancy and adverse birth outcomes: A systematic review and meta-analysis. Environmental Research, 264, 120357. https://doi.org/10.1016/j.envres.2024.120357
Mercury (Hg) is a neurotoxic heavy metal found in various consumer products and environmental sources, making it a major public health concern. Its regulation is critical to protect vulnerable populations from long-term health effects, such as neurological impairment and cardiovascular disease. The HMTC program ensures that products meet the highest standards for mercury safety.
