If you'd like a better understanding of what it takes for sperm to be considered fertile, go grab your measuring spoons and look at the quarter teaspoon. Roughly that amount of ejaculate should boast anywhere between 20 million and 150 million sperm. Anything less than 20 million and fertility just might be an issue.
So Loes Segerink, a researcher at the University of Twente in the Netherlands, has developed a "fertility chip" that can accurately count one's sperm concentration as well as measure its mobility (when discussing sperm the synonym "motility" is often used). What's more, the test can be taken at home, with the ejaculate being, ahem, collected in a more private environment.
While simple home tests are already commercially available, the concentration readings are, well, simple, and indicate only whether sperm concentration is above or below that 20 million mark. But one man's sperm concentration of 19 million is certainly more fertile than another man's count of 1 million.
Segerink, who will be defending her doctoral dissertation in November, says the sperm flows past a liquid-filled channel on the chip beneath electrode "bridges." When cells pass beneath these bridges, a brief fluctuation in electrical resistance occurs. By counting these events, the chip is counting sperm.
To test whether her chip was reading any particles at all, not just sperm, Segerink added tiny microspheres of liquid. The system was selective enough to distinguish sperm from these spheres, as well as to distinguish white blood cells from other bodies.
Actual sperm motility is also an important component of fertility. The chip not only counts sperm, but sorts motile sperm from its dormant brethren, and then tallies up the groups. (Segerink did not report on what percentage of sperm must be motile to be considered fertile.)
To develop this chip, Segerink worked with the BIOS Lab-on-a-Chip research group and collaborated with various companies boasting unusual names, including PigGenetics, Lionix, and Blue4Green. She's now working toward starting a company through which she can continue refining the chip and its read-out device for market use.