Since the dawn of time, the most persistent health issue for humans has been the ramifications of sexual desire: pregnancy, disease, assault and even masturbation and "wet dreams," which medical professionals once believed were harmful to the body. As such, extreme measures have been taken throughout history to curb sexual activity -- whether alone or with someone else. Here is a selection of radical devices that have been designed to do just that.

Pessaries (300s BC - 1900s)
A pessary is a vaginal suppository used to kill sperm and/or block their passage through the cervix. It's one of the oldest contraceptive devices, having been used for over 3,000 years in various cultures. Ancient pessaries were often made from  animal feces (crocodile in Egypt, elephant in India), along with a honey, ground up fruit and bark. Once inserted, the pessary would melt at body temperature and form an impenetrable covering on the cervix. Variations included bowl-shaped fruit rinds that served as a cervical cap, a six-sided "block pessary" with concave sides to cover the cervix, a wishbone "stem pessary" (see above, bottom right) with two prongs brought together for insertion into the cervix and then released to protrude inside the uterus, and cervical plugs made of natural sea sponges, pads of cotton or wool, tree sap or even lumps of opium.

Chastity Belts (1400s-1930s)
Chastity belts were designed to keep women "pure," preventing consensual and non-consensual sexual intercourse (and masturbation) by enclosing the genitalia in a shackle-like contraption. The belts, typically made of leather and metal, featured a locking mechanism and included small holes to allow urination and defecation -- but nothing else.

Amulets and Charms (1500s BC - 1500s)
Perhaps the earliest form of contraception, amulets and charms with reputed powers to prevent conception were used for thousands of years -- granted, with little success. The above left example from ancient Egypt was designed to open and close the womb with a special "key" engraved on the front. Other civilizations used more extreme charms: in ancient Rome, women wore a leather pouch containing a cat's liver on their left foot during sex to prevent pregnancies. During the Middle Ages in Europe, women wore weasel testicles on their thighs or weasel feet (above right) around their necks, while others used wreaths, cat livers, flax soaked in menstrual blood, black cat bones or the anus of a hare.

Male Anti-Masturbation Devices (1870s-1930s)
During the puritanical Victorian era, a popular train of thought held that semen was an "essential oil" in the male body and should be excreted only during marital sexual intercourse, meaning that masturbation was an evil that robbed the body of its vitality and could cause, according to noted Swiss doctor Samuel-Auguste Tissot, "a perceptible reduction of strength, of memory and even of reason; blurred vision, all the nervous disorders, all types of gout and rheumatism, weakening of the organs of generation, blood in the urine, disturbance of the appetite, headaches and a great number of other disorders." As such, a variety of anti-masturbation devices were devised. The male equivalent of a chastity belt, they were typically worn beneath clothing, hooked onto the pants waistband and used to cover the penis and testicles to prevent masturbation ("onanism"). At least one design (see above, bottom right) took it a step further, attaching an ice water reservoir to deter arousal.

Jugum Penis/Spermatorrhoea Ring (1880s-1920s)
Similar in purpose to the male anti-masturbation devices, the Jugum Penis curbed not only masturbation but also specialized in preventing nocturnal emissions, the involuntary release of sperm that was diagnosed in the Victorian era as a disease called "spermatorrhoea" or "seminal weakness." The device was a metal ring with jagged spikes lining the edge pointed inward. A clip was used to attach the ring to the base of the penis, and when an erection increased the penis' girth, it would come in contact with the sharp spikes, causing the wearer enough discomfort to deter ejaculation.

Reusable Condoms (1500s-1900s)
Before the advent of vulcanized rubber in the mid-19th century, condoms were made of materials such as linen, animal membranes (intestines or bladders) and even leather. As such, they were often washed after use, dried and used again. The condom on the left, made of pig intestine, is the oldest in existence, dating back to 1640, and includes a users' manual that advises wearers to immerse the condom in warm milk prior to use in order to help prevent disease. With vulcanized rubber condoms (right), their reusability actually increased because of added durability (at the cost of decreased sensitivity), and reusable condoms remained popular through the early part of the 20th century, as the video below shows:

Lysol (1920s-1960s)
Starting in the 1920s, the makers of Lysol began marketing the household disinfectant as a feminine hygiene product, with ads like these providing testimony from medical experts who, it turns out, didn't exist. By the 1940s, post-coital douching was the most popular form of birth control in America, and Lysol led the pack, its users convinced that the product not only killed germs, but it also killed sperm. By the 1960s, birth control pills diminished the popularity of contraceptive douching, and investigations found that Lysol wasn't an effective form of birth control and could have harsh side effects like inflammation, infection and even death.

Coca-Cola (1950s-1980s)
The rumor that Coca-Cola might be an effective spermicide has been an urban legend since at least the 1950s, originated perhaps as a less expensive (and more easily concealed from parental busybodying) alternative to Lysol contraceptive douching. The soda's fizzy carbonation and its original marketing as a "cure all" medicinal product (see ads above) may have helped spread the belief that a Coke douche after sex could kill sperm and prevent pregnancy -- a legend so widespread that researchers at the Boston University Medical Center tested the product's contraceptive potential in a 1985 study. Strangely, the study found that Coca-Cola was indeed effective in destroying sperm, but the findings have yet to be replicated elsewhere and the project has earned widespread ridicule, including an "Ig Nobel Prize" from Harvard University.