sperma

Sperma, commonly referred to as semen in humans and many animals, is the male reproductive fluid released during ejaculation. The term originates from Ancient Greek sperma, meaning seed. Sperma contains spermatozoa suspended in seminal plasma produced by the male reproductive glands.

Sperma consists of sperm cells produced in the testes and accompanying fluids from the accessory glands, including the seminal vesicles and the prostate. Sperm comprise a minority of the ejaculate, while the majority is fluid that provides nutrients and protective factors. Typical semen volume ranges from about 1.5 to 5 milliliters. The pH is usually around 7.2 to 8.0. Sperm concentration commonly spans 15 to 150 million sperm per milliliter, with total sperm per ejaculate often exceeding 40 million. Seminal plasma contains fructose and other nutrients for energy, as well as enzymes, zinc, citric acid, and prostaglandins that support sperm function and the semen’s properties.

The primary function of sperma is to transport and nourish spermatozoa, enabling their movement through the female reproductive tract to reach an egg. The seminal fluid helps protect sperm from the acidic vaginal environment and provides energy and enzymes that aid in fertilization. In addition, certain components of semen can influence the vaginal milieu and immune responses in the female reproductive tract.

Clinical relevance: Semen analysis is a standard part of fertility evaluation. Reference values guide interpretation, including volume, sperm concentration, total sperm count, progressive motility, and normal morphology. Values outside typical ranges can indicate infertility, infections, or other conditions, though results are influenced by factors such as age, health, lifestyle, and recent sexual activity. Semen can be collected for fertility preservation or used in assisted reproduction.