Two percent of women will have a Bartholin's gland cyst at some point in their lives. They occur at a rate of 0.55 per 1000 person-years and in women aged 35–50 years at a rate of 1.21 per 1000 person-years. The incidence of Bartholin duct cysts increases with age until menopause, and decreases thereafter. Hispanic women may be more often affected than white women and black women. The risk of developing a Bartholin's gland cyst increases with the number of childbirths.

While Bartholin cysts can be quite painful, they are not life-threatening. New cysts cannot absolutely be prevented from forming, but surgical or laser removal of a cyst makes it less likely that a new one will form at the same site. Those with a cyst are more likely than those without a cyst to get one in the future. They can recur every few years or more frequently. Many women who have marsupialization done find that the recurrences may slow, but do not actually stop.

It is estimated that 7% of women in the western world develop palpable breast cysts.

There is preliminary evidence that women with breast cysts may be at an increased risk of breast cancer, especially at younger ages.

In males, the occurrence of breast cysts is rare and may (but need not) be an indication of malignancy.

An epididymal cyst is a cyst of the epididymis containing serous liquid. They are difficult to differentiate from a spermatocele except by aspiration, since a spermatocele contains milky-appearing sperm.

Theca lutein cyst is a type of bilateral functional ovarian cyst filled with clear, straw-colored fluid. To be classified a functional cyst, the mass must reach a diameter of at least three centimeters.

These cysts result from exaggerated physiological stimulation (hyperreactio luteinalis) and are usually associated with markedly elevated levels of beta-human chorionic gonadotropin (beta-hCG). They are thus associated with gestational trophoblastic disease (molar pregnancy), diabetes mellitus, alloimmunisation to Rh-D, and multiple gestations. They have rarely been associated with chronic kidney disease (secondary to reduced hCG clearance) and hyperthyroidism (given the structural homology with TSH). These cysts resolve after pregnancy. Rarely, when the theca-lutein cysts are stimulated by gonadotropins, massive ascites can result. In most cases however, abdominal symptoms are minimal and restricted to peritoneal irritation from cyst hemorrhage. Surgical intervention may be required to remove ruptured or infarcted tissue.

Women who smoke have a twofold increase for functional cysts.

Spermatoceles can originate as diverticulum from the tubules found in the head of the epididymis. Sperm formation gradually causes the diverticulum to increase in size, causing a spermatocele. They are due to continuity between the epididymis and tunica vaginalis.

They are also believed to result from epididymitis, physical trauma, or vasectomy. Scarring of any part of the epididymis can cause it to become obstructed and in turn form a spermatocele.

The development of breast cysts may be prevented to some degree, according to the majority of the specialists. The recommended measures one is able to take in order to avoid the formation of the cysts include practicing good health and avoiding certain medications, eating a balanced diet, taking necessary vitamins and supplements, getting exercise, and avoiding stress.

Although caffeine consumption does not have a scientifically proved connection with the process of cyst development, many women claim that their symptoms are relieved if avoiding it. Some doctors recommend reducing the amount of caffeine in one's diet in terms of both beverages and foods (such as chocolate). Also reducing salt intake may help in alleviating the symptoms of breast cysts, although, again, there is no scientific linkage between these two. Excessive sugar consumption as well as undetected food allergies, such as to gluten or lactose, may also contribute to cyst development.

Spermatocele () is a retention cyst of a tubule of the rete testis or the head of the epididymis distended with barely watery fluid that contains spermatozoa. Small spermatoceles are relatively common, occurring in an estimated 30 percent of all men. They vary in size from several millimeters to many centimeters. Spermatoceles are generally not painful. However, some men may experience discomfort from larger spermatoceles. They are not cancerous, nor do they cause an increased risk of testicular cancer. Additionally, unlike varicoceles, they do not have a negative impact on fertility.

A hydrocele testis is not generally thought to affect fertility. However, it may be indicative of other factors that may affect fertility.

A cyst is a closed sac, having a distinct membrane and division compared with the nearby tissue. Hence, it is a cluster of cells that has grouped together to form a sac (not unlike the manner in which water molecules group together, forming a bubble); however, the distinguishing aspect of a cyst is that the cells forming the "shell" of such a sac are distinctly abnormal (in both appearance and behaviour) when compared with all surrounding cells for that given location. It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, sometimes a cyst may resolve on its own. When a cyst fails to resolve, it may need to be removed surgically, but that would depend upon its type and location.

Cancer-related cysts are formed as a defense mechanism for the body, following the development of mutations that lead to an uncontrolled cellular division. Once that mutation has occurred, the affected cells divide incessantly (and become known as cancerous), forming a tumour. The body encapsulates those cells to try to prevent them from continuing their division and to try to contain the tumour, which becomes known as a cyst. That said, the cancerous cells still may mutate further and gain the ability to form their own blood vessels, from which they received nourishment before being contained. Once that happens, the capsule becomes useless and the tumour may advance from benign to a cancer.

Some cysts are neoplastic and thus, are called cystic tumors; many types are not neoplastic. Some are dysplastic or metaplastic. Pseudocysts are similar to cysts (having a sac filled with fluid), but lack an epithelial lining.

A cyst of Montgomery is a benign breast mass, usually found in adolescent girls. Typically, it resolves spontaneously by itself.

Treatment for dermoid cyst is complete surgical removal, preferably in one piece and without any spillage of cyst contents. Marsupialization, a surgical technique often used to treat pilonidal cyst, is inappropriate for dermoid cyst due to the risk of malignancy.

The association of dermoid cysts with pregnancy has been increasingly reported. They usually present the dilemma of weighing the risks of surgery and anesthesia versus the risks of untreated adnexal mass. Most references state that it is more feasible to treat bilateral dermoid cysts of the ovaries discovered during pregnancy if they grow beyond 6 cm in diameter.

Blocked sebaceous glands, swollen hair follicles, high levels of testosterone and the use of androgenic anabolic steroids will cause such cysts.

A case has been reported of a sebaceous cyst being caused by the human botfly.

Hereditary causes of sebaceous cysts include Gardner's syndrome and basal cell nevus syndrome.

The periareolar glands of Montgomery in the breast are also called Montgomery tubercles or Morgagni tubercles. These periareolar glands are small, papular tissue projections at the edge of the areola (nipple).

Obstruction of the Montgomery tubercles may result in an acute inflammation, a clear or light brownish fluid may drain out of the areola (nipple discharge), and an subareolar mass may develop, the cyst of Montgomery.

A nabothian cyst (or nabothian follicle) is a mucus-filled cyst on the surface of the cervix. They are most often caused when stratified squamous epithelium of the ectocervix (toward the vagina) grows over the simple columnar epithelium of the endocervix (toward the uterus). This tissue growth can block the cervical crypts (subdermal pockets usually 2–10 mm in diameter), trapping cervical mucus inside the crypts.

Nabothian cysts are considered harmless and usually disappear on their own, although some will persist indefinitely. Some women notice they appear and disappear in relation to their menstrual cycle. If a woman is not sure the anomaly she has found on her cervix is a nabothian cyst, a visit to a doctor is recommended to rule out other conditions.

Rarely, nabothian cysts have a correlation with chronic cervicitis, an inflammatory infection of the cervix.

Nabothian cysts are not considered problematic unless they grow very large and present secondary symptoms. A physician may wish to perform a colposcopy or biopsy on a nabothian cyst to check for cancer or other problems. Two methods for removing these cysts include electrocautery and cryofreezing, although new cysts may form after the procedure.

A hydrocele testis is an accumulation of clear fluid in the tunica vaginalis, the most internal of membranes containing a testicle. A primary hydrocele causes a painless enlargement in the scrotum on the affected side and is thought to be due to the defective absorption of fluid secreted between the two layers of the tunica vaginalis (investing membrane). A secondary hydrocele is secondary to either inflammation or a neoplasm in the testis.

A hydrocele usually occurs on one side, but can also affect both sides. The accumulation can be a marker of physical trauma, infection, tumor or varicocele surgery, but the cause is generally unknown. Indirect inguinal hernia indicates increased risk of hydrocele.

A hydrocele is normally seen in infant boys, as an enlarged scrotum. In infant girls, it appears as enlarged labia. However, hydroceles are more common in boys than girls.

Dermoid cysts can appear in young children, often near the lateral aspect of the eyebrow (right part of the right eyebrow or left part of the left eyebrow). Depending on the perceived amount of risk, these are sometimes excised or simply kept under observation.

An inflammatory reaction can occur if a dermoid cyst is disrupted, and the cyst can recur if it is not completely excised. Sometimes complete excision is not practical if the cyst is in a dumbbell configuration, whereby it extends through a suture line in the skull.

If dermoid cysts appear on the medial aspect, the possibility of an encephalocele becomes greater and should be considered among the differential diagnoses.

Dermoid cysts develop during pregnancy. They occur when skin cells and things like hair, sweat glands, oil glands or fatty tissue get trapped in the skin as a baby grows in the womb.Dermoid cysts are present at birth (congenital) and are common. It can be months or years before a dermoid cyst is noticed on a child because the cysts grow slowly.

Dermoid cyst symptoms are minor and the cysts are usually painless. They are not harmful to a child’s health. If they become infected, the infection must be treated and the cyst should be removed. It is easier to remove cysts and prevent scars if the cyst is removed before it gets infected.

Many CNS cysts form in the womb during the first few weeks of development as a result of congenital defects. In adults cysts may also form due to a head injury or trauma, resulting in necrotic tissues (dead tissue), and can sometimes be associated with cancerous tumors or infection in the brain. However, the underlying reasons for cyst formation are still unknown.

One proposed cause of pilonidal cysts is ingrown hair. Excessive sitting is thought to predispose people to the condition, as sitting increases pressure on the coccygeal region. Trauma is not believed to cause a pilonidal cyst; however, such an event may result in inflammation of an existing cyst. However, there are cases where this can occur months after a localized injury to the area. Some researchers have proposed that pilonidal cysts may be the result of a congenital pilonidal dimple. Excessive sweating can also contribute to the cause of a pilonidal cyst. Moisture can fill a stretched hair follicle, which helps create a low-oxygen environment that promotes the growth of anaerobic bacteria, often found in pilonidal cysts. The presence of bacteria and low oxygen levels hamper wound healing and exacerbate a forming pilonidal cyst.

Treatment ranges from simple enucleation of the cyst to curettage to resection. There are cysts—e.g., buccal bifurcation cyst—that resolve on their own, in which just close observation may be employed, unless it is infected and symptomatic.

The thyroglossal tract arises from the foramen cecum at the junction of the anterior two-thirds and posterior one-third of the tongue. Any part of the tract can persist, causing a sinus, fistula or cyst. Most fistulae are acquired following rupture or incision of the infected thyroglossal cyst. A thyroglossal cyst is lined by pseudostratified, ciliated columnar epithelium while a thyroglossal fistula is lined by columnar epithelium.

Thyroglossal Duct Cysts are a birth defect. During embryonic development, the thyroid gland is being formed, beginning at the base of the tongue and moving towards the neck canal, known as the thyroglossal duct. Once the thyroid reaches its final position in the neck, the duct normally disappears. In some individuals, portions of the duct remain behind, leaving small pockets, known as cysts. During a person's life, these cyst pockets can fill with fluids and mucus, enlarging when infected, presenting the thyroglossal cyst.

Most women of reproductive age develop small cysts each month, and large cysts that cause problems occur in about 8% of women before menopause. Ovarian cysts are present in about 16% of women after menopause and if present are more likely to be cancer.

Benign ovarian cysts are common in asymptomatic premenarchal girls and found in approximately 68% of ovaries of girls 2–12 years old and in 84% of ovaries of girls 0–2 years old. Most of them are smaller than 9 mm while about 10-20% are larger macrocysts. While the smaller cysts mostly disappear within 6 months the larger ones appear to be more persistent.

Cysts derived from CNS tissues are very common in America. They are a subtype of cerebrovascular diseases, which are the third leading cause of death in America. Generally, CNS cysts are present in all geographic regions, races, ages, and sexes. However, certain types of CNS cysts are more prevalent in certain types of individuals than others. Some examples of incidence rates in specific types of cysts include:

- Arachnoid cysts are more prevalent in males than females

- Colloid cysts are more prevalent in adults

- Dermoid cysts are more prevalent in children under 10 years of age

- Epidermoid cysts are more prevalent in middle-aged adults