15% of couples of reproductive age have problems achieving a pregnancy, according to data from the Spanish Fertility Society. One of the causes is the delay in conception; Research by the French Institute for Demographic Studies indicates that one in three women between the ages of 35 and 39 will not be able to get pregnant even if they have tried for more than a year. It is estimated that around 40% of infertility cases have their origin in men, and among the factors that contribute to this incapacity of the male, the low mobility of the spermatozoa stands out. Why not ‘tune’ the struggling male gametes to achieve their goal?
This is what a group of German researchers is aiming for, who have developed a tiny hybrid motor made up of polymer micropropellers covered by a metal layer , a propellant that transports sperm with movement problems. Scientists have successfully used their invention to capture, displace, and release immobile male sex cells at desired locations; The experiments have been carried out in channels filled with fluids that mimic natural conditions.
The device is a small coil just the right length and width to attach to the sperm’s tail without trapping its head. Using a rotating magnetic field that is harmless to tissues and sex cells, the researchers have managed to direct their invention towards a sperm that it “traps” and directs to the desired location, where the motor is released.
Laboratory tests have been successful, but scientists recognize that much remains to be done before testing their ingenuity in humans is feasible. They do not yet know how to monitor the process within an organism, so that they can direct the sperm to the ovum; they are also not sure how the woman’s immune system will respond to the micromotors introduced into her body; and the propellants themselves have yet to be improved so as not to cause any damage to the sperm they carry. Everything indicates that, if applied, the first use of these micromotors will be in in vitro fertilization, but the objective of the researchers is that one day they serve in the natural environment of the human body.
Image: An immobile sperm is captured by a remote controlled magnetic helix that directs it on its way to an egg to fertilize it (Mariana Medina-Sánchez et alii).
