**8. Effect on female fertility**

According to WHO documentation more than 10% of women are at the risk of infertility through the exposure of heavy metals such as arsenic which are the major environmental contaminant which may cause reproductive disorders [60]. WHO surveyed that the problem of infertility was pre dominantly greater in female than in males. Ovulation disturbances account for common cause of sub fertility in women [61, 62], as ovulation disturbances are present in uneven or lacking menstrual periods and can overcome through reproductive hormones. The risk of infertility increased in women due to hormonal disturbance, delay ovulation, chromosomal aberration in oocytes by higher exposure level of toxicity. Hormonal imbalance is an important cause of infertility in females due to endocrine disruption by arsenic toxicity which is the major cause of infertility in females (**Figure 2**) [40]. It may also cause cycle abnormality, such as decline in estrus cycle number and elevated duration of diestrus [63]. Ovulation issues, endocrine interference with estrogenic properties may inhibit ovulation and the mid cycle LH surge from pituitary gland in females which may lead to female fertility problems [40, 64]. However, most studies revealed that the arsenic exposure through pesticides and insecticides is the major cause of infertility in females, as these decrease the number of mature follicles and elevate the number of atretic follicles and this indicates potential reduction in fertility [65]. Increased exposure to methylated arsenic may lead to decrease in uterus weight which may affect implantation and increase pre-implantation embryonic loss which leads to infertility in females [66]. A recent study revealed that the women exposed to pesticides have longer menstrual cycle and increased probability of missed periods, as studied in USA; infertile women were observed have three times more exposure to pesticides, in which whole chain of gametogenesis is affected [67].
