Some of the common causes of infertility in men are:
1. Irregular sperm production or lack of sperm, Zero count or low sperm count
2. Hampered sperm delivery due to either erectile dysfunction or early ejaculation
3. Obesity is another reason that may hamper sperm production
4. Certain infections such as Sexually Transmitted Diseases (STDs)
5. Lifestyle conditions such as diet imbalance, addiction to smoking or alcoholism, sedentary lifestyle, or mental and emotional stress. These contribute to poor sperm count.