Health Implications of Microplastic Exposure in Pregnancy and Early Childhood: A Systematic Review.

Microplastics (MPs), defined as plastic particles smaller than 5 mm, have emerged as a significant environmental pollutant, raising concerns about their potential health risks. Emerging evidence shows that MPs can reach human tissues, including the placenta, causing oxidative stress, inflammation, and endocrine disruption These issues are particularly concerning for vulnerable populations like pregnant women and infants, where exposure could negatively impact fetal development and health outcomes. This systematic review, adhering to PRISMA guidelines, aimed to identify and evaluate studies on the impact of microplastic exposure on pregnancy outcomes and early childhood development. A comprehensive search of databases, including Scopus, Web of Science, Medline, and others, along with grey literature and citation searches, was conducted. The review focused on peer-reviewed articles published within the last decade involving human subjects such as newborns, infants, and pregnant women. The systematic search initially identified 328 studies, of which 200 were screened after removing 128 duplicates. From these, 64 full-text articles were assessed for eligibility, and ultimately, 13 studies were included in the final review. Among these, six studies had a low risk of bias, five a moderate risk, and two a high risk of bias. The sample sizes across the studies ranged from 2 to 43 participants, and the most frequently analysed biological material was the placenta (10 out of 13 studies). Microplastics such as polyethylene (PE) and polypropylene (PP) were most detected, appearing in 11 and 10 studies, respectively. Significant associations were observed between microplastic exposure and adverse health outcomes, including reduced birth weight, shortened gestational age, and altered microbiota composition. Methodological variability and potential biases were identified as limitations. Given the increasing global prevalence of microplastic pollution, understanding its health impacts on vulnerable populations such as pregnant women and infants is critical, providing the first comprehensive synthesis of evidence in this area.