Scientific Analysis

Chemical Mechanism

RISUG describes the substance injected into a male’s vasa deferentia. This substance is composed of solvent dimethyl dulphoxide (DMSO) and styrene maleic anhydride (SMA), a compound which allows semen through but damages each sperm cell to the point of ineffectuality (Guha et al. 1997). As each negatively-charged sperm passes through the SMA-coated vasa, it is pushed and pulled by the alternately positive and negative magnetic fields of the RISUG compound. These rapidly flipping forces tear the sperm apart (Jha et al. 2009). After a period of several years the injection may be repeated to ensure continued effective sterilization. The SMA compound can also be neutralized by an injection of sodium bicarbonate or another flush of DMSO, either of which reverses all negative effects on sperm (Lohiya et al. 2010). In theory, the second injection completely returns fertility.

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Developmental Progress

Several institutions and individuals have performed experiments on humans and other animals using various forms of RISUG. Efforts to register the drug under FDA standards in the US are underway, and patents around the globe have been filed despite the incomplete level of testing performed on RISUG operations.

RISUG technology is not currently ready to enter the market as an elective operation. It does, however, possess the potential to become a powerful tool in the world of contraception. It is safe: those side effects that were observed in human subjects were quickly and simply rectified. No human since the Phase I trial has experienced significant negative side effects, and no non-human subject has ever experienced significant ill effects. It is accessible; the procedure itself is scalpel-free and does not require expensive equipment. It is reversible; all recent animal sterilizations have been successfully reversed, and it is very likely that this property of RISUG can be manipulated in humans as well. It is clear that further human trials must be conducted. The long term effects of RISUG must be more fully understood, and experiment must prove the effectiveness of reversal procedures beyond a shred of doubt. This is a serious undertaking, but the current information available about RISUG illustrates in no uncertain terms that this research, however costly, is a sound investment.


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RISUG Review