The intrauterine environment is critical for healthy prenatal growth and affects neonatal survival and later health. Mercury is a toxic metal which can freely cross the placenta and disrupt a wide range of cellular processes. Many observational studies have investigated mercury exposure and prenatal growth, but no prior review has synthesised this evidence. Four relevant publication databases (Embase, MEDLINE/PubMed, PsycINFO, and Scopus) were systematically searched to identify studies of prenatal mercury exposure and birth weight, birth length, or head circumference. Study quality was assessed using the NIH Quality Assessment Tool, and results synthesised in a narrative review. Twenty-seven studies met the review criteria, these were in 17 countries and used 8 types of mercury biomarker. Studies of birth weight (total = 27) involving populations with high levels of mercury exposure, non-linear methods, or identified as high quality were more likely to report an association with mercury, but overall results were inconsistent. Most studies reported no strong evidence of association between mercury and birth length (n = 14) or head circumference (n = 14). Overall, our review did not identify strong evidence that mercury exposure leads to impaired prenatal growth, although there was some evidence of a negative association of mercury with birth weight.
|Journal||International Journal of Environmental Research and Public Health|
|Publication status||Published - 3 Jul 2021|
Bibliographical noteFunding Information:
Funding: This research was funded by the following sources. KD is supported by a Ph.D. studentship from the MRC Integrative Epidemiology Unit at the University of Bristol (faculty matched place for MRC and Peter and Jean James Scholarship). MF has received funding from the VTCT Foundation for a research fellowship with the Cleft Collective at the University of Bristol. CMT is supported by an MRC Career Development Award (MR/T010010/1). AH is supported by grants from the South-Eastern Norway Regional Health Authority (2020022) and the Research Council of Norway (274611). SJL is supported by the NIHR Biomedical Research Centre at University Hospitals Bristol and Weston NHS Foundation Trust and the University of Bristol.
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
- systematic review
- birth weight
- birth length
- head circumference
- prenatal growth