Voronoff was a student of French surgeon, biologist, eugenicist, and Nobel Prize recipient Alexis Carrel, from whom he learnt surgical techniques of transplantation.

[7] Ten years later, Voronoff married Gerti Schwartz, believed by some to be the illegitimate daughter of King Carol of Romania.

[9] On the other hand, TimesDaily was more positive, calling him a "famed prononent proponent of rejuvenation for humans through monkey glands" and claiming that he actually became more popular later in life: "Medical authorities at first rejected his theories, but later developments confirmed some of his ideas.

Bostwick also acted as his laboratory assistant at the Collège de France in Paris, and consequently became the first woman admitted to that institution.

Between 1917 and 1926, Voronoff carried out over five hundred transplantations on sheep and goats, and also on a bull, grafting testicles from younger animals to older ones.

Voronoff also speculates that the grafting surgery might be beneficial to people with "dementia praecox", the mental illness known today as schizophrenia.

[21][22] The poet E. E. Cummings sang of a "famous doctor who inserts monkeyglands in millionaires", and Chicago surgeon Max Thorek, for whom the Thorek Hospital and Medical Center is named, recalled that soon, "fashionable dinner parties and cracker barrel confabs, as well as sedate gatherings of the medical élite, were alive with the whisper - 'Monkey Glands'.

"[23] By the early 1930s, over 500 men had been treated in France by his rejuvenation technique (including Voronoff's younger brother Georges[24]), and thousands more around the world, such as in a special clinic set up in Algiers.

[26][27][28] To cope with the demand for the operation, Voronoff set up his own monkey farm in Ventimiglia, on the Italian Riviera, employing a former circus-animal keeper to run it.

[29] With his growing wealth, Voronoff occupied the whole of the first floor of one of Paris's most expensive hotels, surrounded by a retinue of chauffeurs, valets, personal secretaries and two mistresses.

In his book The Monkey Gland Affair, David Hamilton, an experienced transplant surgeon, discusses how animal tissue inserted into a human would not be absorbed, but instantly rejected.

Voronoff believed that at some point, scientists would discover what substance the testicular glands secrete, making grafting surgery unnecessary.

[34] Kozminski and Bloom (2012) wrote that Voronoff's experiments were "plagued by secrecy, subjectivity and sensationalism", adding that the era of testosterone surgery was ended by a "lack of verifiable data".

[34] They write that Voronoff and others can be faulted for "paternalistic use of patients and misogynistic message of testicular power", but that efforts such as these in the history of urology may have helped fuel medical progress.

"[35] In 2005, Kahn stated that the work by Voronoff and others in the 1920s and 1930s therapies that "received widespread [...] ridicule in the popular press, were spread rapidly by practitioners of questionable training and ethical motivation, and finally and relatively quickly disappeared from common use".

[38] "The Adventure of the Creeping Man" is a Sherlock Holmes short story by Arthur Conan Doyle, first published in March 1923 but set in 1903.

The song "Monkey-Doodle-Doo", written by Irving Berlin and featured in the Marx Brothers film The Coconuts, contains the line: "If you're too old for dancing/Get yourself a monkey gland".

Strange-looking ashtrays depicting monkeys protecting their private parts, with the phrase (translated from French) "No, Voronoff, you won't get me!"

In his autobiography A Chef's Tale, Pierre Franey relates how when Voronoff dined at Le Pavillon in the 1940s, waiters would remark how "he looked like a monkey himself, with his exceptionally long fingers and slouching walk.