Among the bibliographic curiosities I have been collecting for years, there is also a little book entitled L’amico discreto. It’s the 1862 Italian translation of The silent friend (1847) by R. e L. Perry; aside from 100 beautiful anatomical plates, the book also shows a priceless subtitle: Observations on Onanism and Its Baneful Results, Including Mental and Sexual Incapacity and Impotence.

Just by skimming through the table of contents, it’s clear how masturbation was indicated as the main cause for a wide array of conditions: from indigestion to “hypoconriac melancholy”, from deafness to “bending of the penis”, from emaciated complexion to the inability to walk, in a climax of ever more terrible symptoms preparing the way for the ultimate, inevitable outcome — death.
One page after the other, the reader learns why onanism is to be blamed for such illnesses, specifically because it provokes an

excitement of the nervous system [which] by stimulating the organs to transient vigour, brings, ere middle life succeeds the summer of manhood, all the sensible infirmities and foibles of age; producing in its impetuous current, such an assemblage of morbid irritation, that even on trivial occasions its excitement is of a high and inflammable character, and its endurance beyond the power of reason to sustain.

But this is just the beginning: the worst damage is on the mind and soul, because this state of constant nervous stimulation

places the individual in a state of anxiety and misery for the remainder of his existence, — a kind of contingency, which it is difficult for language adequately to describe; he vegetates, but lives not: […] leading the excited deviating mind into a fertile field of seductive error — into a gradual and fatal degradation of manhood — into a pernicious, disgraceful, and ultimately almost involuntary application of those inherent rights which nature wisely instituted for the preservation of her species […] in defiance of culture, moral feeling, moral obligation, and religious impressions: thus the man, who, at the advent of youth and genius was endowed with gaiety and sociality, becomes, ere twenty-five summers have shed their lustre on him, a misanthrope, and a nadir-point of discontent! What moral region does that man live in? […] Is it nothing to light the gloomy torch that guides, by slow and melancholy steps to the sepulchre of manhood, in the gay and fascinating spring-time of youth and ardent desire; when the brilliant fire of passion, genius, and sentiment, ought to electrify the whole frame?

This being a physiology and anatomy essay, today its embellishments, its evocative language (closer to second-rate poetry than to science) seem oddly out of place — and we can smile upon reading its absurd theories; yet The Silent Friend is just one of many Nineteeth Century texts demonizing masturbation, all pretty popular since 1712, when an anonymous priest published a volume called Onania, followed in 1760 by L’Onanisme by Swiss doctor Samuel-Auguste Tissot, which had rapidly become a best-seller of its time.
Now, if physicians reacted in such a harsh way against male masturbation, you can guess their stance on female auto-eroticism.

Here, the repulsion for an act which was already considered aberrant, was joined by all those ancestral fears regarding female sexuality. From the ancient vagina dentata (here is an old post about it) to Plato’s description of the uterus (hystera) as an aggressive animale roaming through the woman’s abdomen, going through theological precepts in Biblical-Christian tradition, medicine inherited a somber, essentially misogynistic vision: female sexuality, a true repressed collective unconscious, was perceived as dangerous and ungovernable.
Another text in my library is the female analogue of Tissot’s Onania: written by J.D.T. de Bienville, La Ninfomania ovvero il Furore Uterino (“Nymphomania, or The Uterine Fury”) was originally published in France in 1771.
I’m pasting here a couple of passages, which show a very similar style in respect to the previous quotes:

We see some perverted young girls, who have conducted a voluptuous life over a long period of time, suddenly fall prey to this disease; and this happens when forced retirement is keeping them from those occasions which facilitated their guilty and fatal inclination. […] All of them, after they are conquered by such malady, occupy themselves with the same force and energy with those objects which light in their passion the infernal flame of lewd pleasure […], they indulge in reading lewd Novels, that begin by bending their heart to soft feelings, and end up inspiring the most depraved and gross incontinence. […] Those women who, after taking a few steps in this horrible labyrinth, miss the strength to come back, are drawn almost imperceptibly to excesses, which after corrupting and damaging their good name, deprive them of their own life.

The book goes on to describe the hallucinatory state in which the nymphomaniacs fall, frantically hurling at men (by nature all chaste and pure, it seems), and barely leaving them “the time to escape their hands“.
Of course, this an Eighteenth Century text. But things did not improve in the following century: during the Nineteenth Century, actually, the ill-concealed desire to repress female sexuality found one of its cruelest incarnations, the so-called “extirpation”.

This euphemism was used to indicate the practice of clitoridectomy, the surgical removal of the clitoris.
Everybody kows that female genital mutilations continue to be a reality in many countries, and they have been the focus of several international campaigns to abandon the practice.
It seems hard to believe that, far from being solely a tribal tradition, it became widespread in Europe and in the United States within the frame of modern Western medicine.
Clitoridectomy, a simple yet brutal operation, was based on the idea that female masturbation led to hysteria, lesbianism and nymphomania. The perfect circular reasoning behind this theory was the following: in mental institutions, insane female patients were often caught masturbating, therefore masturbation had to be the cause of their lunacy.

One of the most fervent promoters of extirpation was Dr. Isaac Baker Brown, English gynaecologist and obstetrical surgeon.
In 1858 he opened a clinic on Notting Hill, ad his therapies became so successful that Baker Brown resigned from Guy’s Hospital to work privately full time. By means of clitoridectomy, he was able to cure (if we are to trust his own words) several kinds of madness, epilepsy, catalepsy and hysteria in his patients: in 1866 he published a nice little book on the subject, which was praised by the Times because Brown “brought insanity within the scope of surgical treatment“. In his book, Brown reported 48 cases of female masturbation, the heinous effects on the patients’ health, and the miraculous result of clitoridectomy in curing the symptoms.

We don’t know for sure how many women ended up under the enthusiastic doctor’s knife.
Brown would have probably carried on with his mutilation work, if he hadn’t made the mistake of setting up a publicity campaign to advertise his clinic. Even then, self-promotion was considered ethically wrong for a physician, so on April 29, 1866, the British Medical Journal published a heavy j’accuse against the doctor. The Lancet followed shortly after, then even the Times proved to have changed position and asked if the surgical treatment of illness was legal at all. Brown ended up being investigated by the Lunacy Commission, which dealt with the patients’ welfare in asylums, and in panic he denied he ever carried out clitoridectomies on his mentally ill patients.

But it was too late.
Even the Royal College of Surgeons turned away from him, and a meeting decided (with 194 approving votes against 38 opposite votes) his removal from the Obstetric Society of London.
R. Youngson and I. Schott, in A Brief History of Bad Medicine (Robinson, 2012), highlight the paradox of this story:

The extraordinary thing was that Baker Brown was disgraced, not because he practised clitoridectomy for ridiculuous indications, but because, out of greed, he had offended against professional ethics. No one ever suggested that there was anything wrong with clitoridectomy, as such. Many years were to pass before this operation was condemned by the medical profession.

And many more, until eventually masturbation could be freed from medical criminalization and moral prejudice: at the beginning of the Twentieth Century doctors still recommended the use of constrictive laces and gears, straight-jackets, up to shock treatments like cauterization or electroconvulsive therapy.

1903 patent to prevent erections and nocturnal pollutions through the use of spikes, electric shocks and an alarm bell.

Within this dreadful galaxy of old anti-masturbation devices, there’s one looking quite harmless and even healthy: corn flakes, which were invented by famous Dr. Kellogg as an adjuvant diet against the temptations of onanism. And yet, whenever cereals didn’t do the trick, Kellogg advised that young boys’ foreskins should be sewn with wire; as for young girls, he recommended burning the clitoris with phenol, which he considered

an excellent means of allaying the abnormal excitement, and preventing the recurrence of the practice in those whose will-power has become so weakened that the patient is unable to exercise entire self-control.
The worse cases among young women are those in which the disease has advanced so far that erotic thoughts are attended by the same voluptuous sensations that accompany the practice. The author has met many cases of this sort in young women, who acknowledged that the sexual orgasm was thus produced, often several times daily. The application of carbolic acid in the manner described is also useful in these cases in allaying the abnormal excitement, which is a frequent provocation of the practice of this form of mental masturbation.

(J. H. Kellogg, Plain Facts for Old And Young, 1888)

It was not until the Kinsey Reports (1948-1953) that masturbation was eventually legitimized as a natural and healthy part of sexuality.
All in all, as Woody Allen put it, it’s just “sex with someone you love“.

On the “fantastic physiology” of the uterus, there is a splendid article (in Italian language) here. Wikipedia has also a page on the history of masturbation. I also recommend Orgasm and the West. A History of Pleasure from the Sixteenth Century to the Present, by R. Muchembled.