The procedure called RISUG in India (reversible inhibition of sperm under guidance) takes about 15 minutes with a doctor, is effective after about three days, and lasts for 10 or more years. A doctor applies some local anesthetic, makes a small pinhole in the base of the scrotum, reaches in with a pair of very thin forceps, and pulls out the small white vas deferens tube. Then, the doctor injects the polymer gel (called Vasalgel here in the US), pushes the vas deferens back inside, repeats the process for the other vas deferens, puts a Band-Aid over the small hole, and the person is on their way. If this all sounds incredibly simple and inexpensive, that’s because it is. The chemicals themselves cost less than the syringe used to administer them. But the science of what happens next is the really fascinating part.