Prenatal mercury exposure and birth outcomes

Area of Science:

• Environmental Health
• Perinatal Epidemiology
• Toxicology

Background:

• Inconsistent findings exist regarding mercury exposure, birth anthropometry, gestational length, and placental weight.
• The influence of seafood consumption on these associations remains unclear.

Purpose of the Study:

• To investigate the association between prenatal total mercury (T-Hg) exposure and birth outcomes in a high-seafood-consuming population.
• To assess T-Hg's impact on anthropometry at birth, placental weight, and gestational length.

Main Methods:

• Cord blood T-Hg levels were measured in 1869 newborns from the Spanish INMA cohort (2004-2008).
• Adjusted linear and Cox regression models evaluated associations between T-Hg and birth outcomes.
• Meta-analysis was used to obtain final estimates.

Main Results:

• A doubling of T-Hg was linked to a 7.7g decrease in placental weight and marginally to reduced head circumference.
• Inverse relationships were observed between T-Hg and fetal weight and length, though less pronounced.
• No significant association was found between mercury exposure and gestational length.

Conclusions:

• Prenatal mercury exposure may negatively affect placental and fetal growth.
• Fish intake can confound the relationship between mercury exposure and adverse birth outcomes.