In-vitro fertilization is certainly a potential avenue for couples who are having problems conceiving a child due to low-quality sperm. However, the unfortunate fact of the matter is that this method is quite expensive and is often unsuccessful. Thanks to a team of scientists in Australia, a straightforward new technology that picks out the most capable sperm for the job has emerged.

Identifying the strongest swimmers

There are already established ways for identifying which sperm have the best swimming abilities and which are less likely to succeed in fertilizing an egg.

A method known as the swim-up involves placing a sperm-friendly medium on top of a sample of sperm that is contained within a test tube. This combination is then left to sit for approximately one hour. Only the sperm that are in the best possible health will be able to swim to the surface of that medium to be collected.

Another approach, termed density gradient centrifugation, involves placing a sample of sperm at the very top of a test tube filled with liquids of varying densities. When the test tube is placed in a centrifuge, the sperm that are in the best of health will sink to the bottom of the tube, where they will meet the denser liquids, while the sperm that are in the worst of health will become trapped in the upper layers.

Unfortunately, according to research conducted by academics at the University of Technology Sydney (UTS) in Australia, both approaches can result in the breakdown of DNA and the death of cells as a direct result of the production of reactive oxygen species. This is where the recently developed, disc-shaped polymer gadget that was manufactured via 3D printing comes into play.

The microfluidic sperm selection device

A team of scientists from UTS, collaborating with researchers from the UTS-born start-up NeoGenix Biosciences, created and tested this new microfluidic sperm selection device.

It features a reservoir around the perimeter, which is connected to a central collection well via complicated microfluidic channels. The female reproductive canal inspired the design of this device. When a sample of sperm is deposited in the reservoir, the idea is that only the healthiest and most active sperm will make it through the channels and into the well. Reportedly, it works exactly as intended.

“We conducted extensive testing against conventional IVF [in-vitro fertilization] selection methods, with the new method showing an 85 percent improvement in DNA integrity and an average 90 percent reduction in sperm cell death,” reported one of the scientists involved in the study, Prof. Majid Warkiani. “The sperm selected by our method also demonstrated better recovery after freezing than traditional methods.”

Source study: Nature— Sperm quality metrics were improved by a biomimetic microfluidic selection platform compared to swim-up methods