Another important sperm test measures “sperm function”. The Acrosome Reaction (AR) test measures the ability of sperm to release the enzymes in their acrosomal caps, a necessary step for egg fertilization. This test has been validated by studies comparing AR test results with actual fertilization rates in human IVF (in vitro fertilization). There is a direct correlation between the ability of sperm to undergo the acrosome reaction and their ability to fertilize eggs in the laboratory. We find this information essential when deciding on a treatment plan. Patients with a good AR result may be able to achieve conception through more conventional treatments whereas those with a poor AR result would do better with IVF and ICSI ( intracytoplasmic sperm injection).