Vasovasostomy is a microsurgical procedure to restore fertility after vasectomy, a surgery that sterilizes the patient by severing the vas deferentia, the tubes that carry the sperm from the testes to the penis. After a vasectomy, a patient may have various reasons for wanting to reverse the procedure, such as new opportunities for having children or a new romantic partnership. A vasovasostomy involves reestablishing the flow of sperm through the vas deferens by reconnecting the severed ends of the tube. In 1919, in the United States, William C. Quinby performed the first recorded successful vasovasostomy. Modern improvements on the surgery have led to its adoption as a microsurgery, a procedure that involves a microscope and specialized microscopic instruments. Surgical research over the twentieth century into reconnecting a blocked vas deferens and the resulting microsurgical technique for vasovasostomy has provided a way for people to regain their fertility after a vasectomy.

In 2021, the World Health Organization, or WHO, published the sixth edition of their Laboratory Manual for the Examination and Processing of Human Semen, which provides standardized guidelines to physicians and other medical professionals performing semen analysis. Semen analysis is a technique that medical professionals use to analyze the characteristics of a male’s semen and sperm cells to identify possible causes of male infertility. A sperm cell is the male sex cell that fertilizes a female’s egg cell, while semen is the fluid containing sperm cells that men release during ejaculation. The WHO created the first laboratory manual for semen analysis in 1980, a time when there was no standardized way to analyze a male’s semen sample. The WHO laboratory manual was one of the first documents to standardize a procedure for evaluating human semen to look for sperm abnormalities, and it remains one of the most widespread methods of evaluating a male’s fertility potential and determining the causes of male infertility.