Infertility may result from an issue with either a male, female, or both. In this blog, we will focus on 10 major reasons of male infertility that do not manifest obvious and visible symptoms.

1. Varicocoele - An enlargement of the veins within the loose bag of skin that holds your testicles (scrotum). A varicocele increases the temperature of the testes and is similar to a varicose vein you might see in your leg. Varicocele is a common cause of low sperm production and decreased sperm quality.

2. Obesity - A Body Mass Index (BMI) over 30 might decreases the quality of sperm as obesity has a significant impact on the metabolism of androgens such as testosterone. 

3. Age - After 35, since DNA of the nucleus fragments, reproductive capacity of a man decreases dramatically. 

4. Infections - Sexually Transmitted Infections (STIs), such as gonorrhea, chlamydia and HIV can cause male infertility. Genital inflammation produced by these microorganisms contribute to the changes in sperm quality, while severe and chronic cases of these infections can cause obstruction. Some of the STIs can be life threatening, therefore in case of suspicious behavior, it is the best idea to get tested. 

5. Addictive substances - Smoking, alcohol and drugs significantly influence the quality and production of sperm. Nicotine causes an imbalance in the body which is called oxidative stress; this influences sperm quality and fertilisation potential. Cocaine also distorts sperm development and motility.

6. Radiation -  It is highly recommended that men do not place their mobile phones close to the scrotum and testicles to reduce risk of infertility. In case of chemotherapy, sperm freezing and other advanced methods like testicular biopsy or spermatogonial stem cell extraction and freezing are recommended.