The effects of exposure to microplastics on female reproductive health and pregnancy outcomes: A systematic review and meta-analysis

Microplastic pollution is one of the most important challenges to public health. The current study aimed to assess the impact of microplastic accumulation on female reproductive health and pregnancy outcomes. A comprehensive search was conducted in databases, including ISI Web of Science, PubMed, Scopus, and Google Scholar, to evaluate the effects of microplastic contamination on reproductive health and fetal outcomes. Thirteen studies met our criteria. Microplastic pollution was found in samples of placenta, meconium, amniotic fluid, and feces. In total, 10 polymers were identified, among which polystyrene, polyurethane, and polyamide polymers were the most abundant. The average size of the microplastics was 2.1-100 micrometers. The contamination rate with microplastics was measured at about an event rate of 87 % (95 % CI: 80.0-91.2). It was found that microplastic content in human reproductive tissue has nothing to do with the mode of delivery. Also, the results showed that consuming food in plastic containers increased the chance of contamination with microplastics in pregnant women (95 % CI: 1.32-21.9; OR: 5.39). The clinical elevation of microplastic accumulation with adverse pregnancy outcomes has shown a significant correlation between microplastic content in the placenta and gestational age (95 % CI: 0.03-0.22; OR: 0.89). In addition, microplastic pollution in the placenta significantly increases the risk of intrauterine growth restriction (IUGR) (95 % CI: 2.07-8.06; OR: 5.06). Microplastics may be a risk factor that contributes to human reproductive health issues and pregnancy-related outcomes; further large-scale investigations are needed to confirm the current findings.