In the United States about 20% of children will develop pinworm at some point. Infection rates among high-risk groups may be as high as 50%. It is not considered a serious disease. Pinworms are believed to have affected humans throughout history. Signs and symptoms
One-third of individuals with pinworm infection are totally asymptomatic. The main symptoms are itching in and around the anus and perineum. The itching occurs mainly during the night, and is caused by the female pinworms migrating to lay eggs around the anus. Both the migrating females and the clumps of eggs are irritating, as well as the sticky substance that is produced by the worms when the eggs are laid. The intensity of the itching varies, and it can be described as tickling, crawling sensations, or even acute pain. The itching leads to continuously scratching the area around the anus, which can further result in tearing of the skin and complications such as secondary bacterial infections, including bacterial skin inflammation, and hair follicle inflammation. General symptoms are trouble sleeping, and restlessness. A considerable proportion of children experience loss of appetite, weight loss, irritability, emotional instability, and bed wetting.Pinworms cannot damage the skin, and they do not normally migrate through tissues. However, they may move onto the vulva and into the vagina, from there moving to the external orifice of the uterus, and onwards to the uterine cavity, fallopian tubes, ovaries, and peritoneal cavity. This can cause inflammation of the vulva and vagina. This causes vaginal discharge and itchiness of the vulva.
Invasive hydatidiform mole is a type of neoplasia that grows into the muscular wall of the uterus. It is formed after conception (fertilization of an egg by a sperm). It may spread to other parts of the body, such as the vagina, vulva, and lung. See also
Hydatidiform mole

References
External links
Chorioadenoma destruens entry in the public domain NCI Dictionary of Cancer Terms This article incorporates public domain material from the U.S. National Cancer Institute document: "Dictionary of Cancer Terms".