Sperm motility refers to the ability of sperm cells to move effectively. This movement is crucial for fertilization, as sperm must travel through the female reproductive tract to reach and fertilize an egg. Sperm motility is typically assessed by observing the speed and direction of sperm movement. Several factors can influence sperm motility, including temperature, pH levels, and the presence of certain nutrients. Healthy sperm usually exhibit progressive motility, meaning they move in a straight line or large circles. Poor motility can lead to challenges in conception and may be a sign of underlying health issues.