The simple answer to this is, NO. Not releasing sperm cannot in any way affect your health or sexual life. However, there are few cases where it might not be, and that’s depending on the cause. The truth is that you don’t need to release a lot of sperm to reach orgasm. Contrary to what people already believe, it isn’t a must for you to reach orgasm before you ejaculate. They are two independent processes; you can do one without having to do the other. When you avoid ejaculation intentionally or semen retention, the process is called the act of abstaining. Those who practice tantric sex can relate better to this because that is what they practice. To effectively abstain from ejaculating for a certain period, you would need to avoid getting engaged in any form of sexual activity, or you can simply train yourself and try not to ejaculate whenever you reach orgasm. Most people abstain from ejaculation due to different reasons. For some people, it’s more of spiritual practice, and for others, it’s about emotional growth. Other people do it because they are trying to boost their fertility, and others believe that not ejaculating would help them grow muscles. To date, there have been no documented side effects of retaining sperm, so if you feel that’s your thing, then, by all means, you can proceed. However, some medical conditions can cause you not to ejaculate during sexual intercourse, or while masturbating.