Evaluation of the presence of microplastics using various parameters in placenta samples of patients with assisted reproductive techniques and spontaneous pregnancy

Plastics emerge in various aspects of our lives due to their characteristics such as being lightweight, flexible, easily processed, user-friendly, and economical. These products, which are not easily decomposed in nature, gradually break down into smaller plastic particles over time. Microplastics are plastic particles ranging in size from 0.001 to 5 mm, resulting from the degradation of plastics' chemical structures that mingle with nature. In our daily lives, consciously or unconsciously, we encounter numerous sources of microplastics. Microplastics, which mix with the food chain through sources such as consumption and cosmetic products, textile products, and industrial raw materials from all aspects of life, are introduced into ecosystems through soil, air, and water and accumulate in the tissues of living organisms through the food chain. Microplastics, posing potential risks to all living organisms, have been detected in biological samples such as blood, lungs, liver, kidneys, spleen, sputum, feces, placenta, and breast milk in humans. In this doctoral thesis, the presence of microplastics in placental samples obtained from mothers who became pregnant through assisted reproductive techniques due to infertility diagnosis is investigated and compared with those obtained from mothers who became pregnant spontaneously without any treatment. Infertility, which has become one of the significant public health pathologies in our country as well as globally, refers to the inability to achieve pregnancy despite unprotected regular sexual intercourse for at least 12 months. According to the literature review conducted, it has been found that no study has been conducted regarding the effect of microplastic exposure on human tissues on infertility. In this study, the presence of microplastics in placental samples obtained from fertile and infertile groups was investigated using discriminative methods such as Fourier Transform Infrared (FTIR) Spectroscopy, Raman Spectroscopy, Scanning Electron Microscopy (SEM), and Energy-Dispersive Spectroscopy (EDS). Microplastic derivatives such as PE, PP, PS, PET, and PU were detected in placental samples, with trace levels found to be slightly higher in the infertile group. This study is the first to compare the presence of microplastics in fertile and infertile groups using human placental samples. However, factors such as ethical considerations, difficulties in clinical practices, and the living standards, dietary habits, and susceptibility to plastic use of volunteer expectant mothers involved in the study restrict the research's scope. It is believed that conducting research with comprehensive and larger samples in future processes will clarify the effects of microplastics on reproductive health, infertility, and pregnancy processes.