Iodine is associated to semen quality in men who undergo consultations for infertility

- The scientific question asked: Is iodine intake related to male infertility, independently of thyroid hormones?.
- The principal new findings: Men with higher semen iodine levels had more morphological alteration in spermatozoa. Men with higher urinary iodine had a lower motile sperm count.
- The significance of these findings to the field: This study brings a new approach to the study of infertile couples. The cause-effect relationship needs to be explored further in other type of study.

The role that adequate iodine intake could have on the male reproductive function is not entirely known. The aim of this study is to determine whether there is a relation between male infertility and urinary and semen iodine levels in 96 couples who underwent consultation for infertility. The median of semen iodine was higher in men who consumed iodized salt than in those who consumed non-iodized salt (p = 0.019). Men with a higher semen iodine level had more morphological alterations in spermatozoa (p = 0.032). Men with a higher urinary iodine level had a lower motile sperm count according to the “direct swim-up” technique (p = 0.044). Men >3 years without successfully achieving pregnancy had a higher urinary iodine level than those with ≤ 3 years (p = 0.035). In conclusion, iodine may play a role in the quality of semen: an increase in semen iodine levels is associated with different variables related to male infertility.