Infertility is a severe medical problem and is considered a serious global public health issue affecting a large proportion of humanity. Oxidative stress is one of the most crucial factors involved in infertility. Recent studies indicate that the overproduction of reactive oxygen species (ROS) or reactive nitrogen species (RNS) may cause damage to the male and female reproductive systems leading to infertility. Low amounts of ROS and RNS are essential for the normal functioning of the male and female reproductive systems, such as sperm motility, acrosome reaction, interactions with oocytes, ovulation, and the maturation of follicles. Environmental factors such as heavy metals can cause reproductive dysfunction in men and women through the overproduction of ROS and RNS. It is suggested that oxidative stress caused by arsenic is associated with male and female reproductive disorders such as through the alteration in sperm counts and motility, decreased sex hormones, dysfunction of the testis and ovary, as well as damage to the processes of spermatogenesis and oogenesis. This review paper highlights the relationship between arsenic-induced oxidative stress and the prevalence of infertility, with detailed explanations of potential underlying mechanisms.

Polycystic ovary syndrome (PCOS) is a widespread endocrine disorder among fertile women and may be induced by nutritional deficiencies. In this study, we assess the impact of selenium supplementation (SS) on biochemical markers in women with PCOS. To gather relevant literature, we searched the Web of Science, Cochrane Library, Scopus, Embase, and MEDLINE databases from inception up to July 24, 2022. Subsequently, we included all published full-text randomized clinical trials examining the effects of SS versus placebo on biochemical changes in women with PCOS. Review Manager 5.3 was used to collect and analyze data and assess the risk of bias. Seven articles, comprising 413 women, were ultimately involved in the study. According to the results, SS could increase the level of quantitative insulin sensitivity check index [standardized mean difference (SMD)=0.34, 95% confidence interval (CI)=0.04∼0.65], total antioxidant capacity (SMD=0.89 mmol/L, 95% CI=0.52∼1.26), and glutathione (SMD=1.00 μmol/L, 95% CI=0.22∼1.78). Conversely, SS could decrease triglyceride, cholesterol, fasting plasma glucose, insulin, and the homeostasis model of assessment-insulin resistance levels compared with the placebo. Furthermore, there were no significant differences regarding sex hormone-binding globulin level, testosterone level, malondialdehyde, and body mass index between the two groups. In addition, the results suggest that SS improves biochemical markers in women with PCOS and thus is recommended for treating biochemical disorders among these women in addition to standard treatment.