Behrooz Karimi, Maryam Shokarpour, Nazila Najdi, Katayoun Vakilian, Mohammad Javad Ghanadzadeh, Marjan Mahlouji,
Volume 18, Issue 3 (12-2025)
Background and Objective: Heavy metals such as lead, cadmium, and mercury, due to their bio-accumulative properties, pose significant risks to maternal and fetal health. This study investigated the association between exposure to these metals among pregnant women in Arak and adverse birth outcomes, including infant birth weight and growth status.
Materials and Methods: A cross-sectional study was conducted among 235 pregnant women residing in Arak in 2024. Inclusion criteria were residence in Arak, age under 18 years, and absence of psychological or cognitive disorders; exclusion criteria included migration or leaving the city during the study period. Participants were evaluated at two intervals: the first and second halves of pregnancy. Demographic and clinical data were collected, and urinary concentrations of lead, cadmium, and mercury were measured. The effects of metal exposure on birth weight and growth status, including small-for-gestational-age (SGA) and large-for-gestational-age (LGA), were assessed using linear and logistic regression models adjusted for maternal age, education, and body mass index.
Results: The mean birth weight was 3,232.5 g; 10.64%of infants were classified as SGA, and 3.40%as LGA. The mean urinary concentrations of lead, mercury, and cadmium were 0.48±0.84 μg/L, 2.64 ±1.40 μg/L, and 0.36±0.80 μg/L, respectively. Cadmium exposure during both phases of pregnancy was associated with reduced birth weight, while lead showed negative effects during late pregnancy. In early pregnancy, lead (OR =1.026) and cadmium (OR = 1.044) were associated with an increased risk of SGA, whereas mercury (OR = 1.042) was associated with LGA.
Conclusion: Cadmium and lead exposure reduce birth weight and increase risks of SGA and LGA, highlighting the need to minimize maternal exposure to heavy metals.
