09/23/2022

Sperm Swim Together To Help Each Other Reach The Egg

11:00 minutes

an illustration of an egg on the right, with many sperm swimming towards it from the left side
Credit: Shutterstock

New research is complicating our understanding of how, exactly, sperm are able to reach eggs. The predominant theory is that sperm compete against each other, with the strongest swimmer fertilizing the egg.

But a new study, using cow sperm, suggests that sperm might actually swim together, forming clusters to help each other swim upstream to reach the egg.

Researchers created a device that has some of the features of a female reproductive tract, which they tested using a polymer substance that mimics cervical mucus. The intensity of the flow of this mucus-like fluid influenced how well the sperm clustered together. The faster the flow, the more likely the sperm were to band together to swim upstream.

Ira talks with Dr. Chih-Kuan Tung, associate professor of physics at North Carolina Agricultural and Technical State University about his research on sperm motility, and how it could improve infertility testing in the future.


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Segment Guests

Chih-Kuan Tung

Dr. Chih-Kuan Tung is an associate professor of Physics at North Carolina A&T State University in Greensboro, North Carolina.

Segment Transcript

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