First evidence of microplastics in human ovarian follicular fluid: an emerging threat to female fertility

Abstract Plastic pollution is a pressing global issue, with over 400 million tons produced annually and projections of 1.1 billion tons by 2050. Microplastics (MPs), ranging from 5 mm to 1 µm, are pervasive in the environment. They are found in air, sea, freshwater, soils, food chains and studies show that tiny MPs, smaller than 10 μm, can cross cellular membranes, posing potential health risks through oxidative stress, inflammation, immune dysfunction, neurotoxicity and reprotoxicity. In recent years, research has shown that microplastics have negative effects on the female reproductive systems of animals. However, there is still a lack of evidence on how the accumulation of microplastics affects the reproductive health of human females. This study aimed to examine the presence of microplastics in the ovarian follicular fluid of 18 women undergoing assisted reproductive treatment whose samples were processed using a patented method endorsed nationally and internationally. Plastic particles <10 µm were measured using SEM with EDX detection. Preventive measures were taken to avoid contamination during the process. Microplastics (dimensions <10 µm) were detected in 14 out of 18 samples of follicular fluid, with an average of 2191 p/ml (0 - 7181p/ml) and with a mean diameter of MPs of 4.48 µm (3.18-5.54 µm). A significant correlation was found between microplastic concentration and FSH (p-value <0.05), as well as a weak correlation with BMI, age and Estradiol. There was no correlation with fertilization outcomes, miscarriages, or live birth. This is the first study to provide evidence for microplastics’ presence in ovarian follicular fluid in women undergoing assisted reproductive treatment, representing a potential threat to female reproductive function. Abstract Figure