Anogenital Warts

Anogenital warts are small growths that appear on or around the genitals and anus, caused by certain types of human papillomavirus (HPV). While they’re one of the most common sexually transmitted infections, treatment options are available, and vaccines can help prevent them.

Table of contents

• What are anogenital warts?
• What causes anogenital warts?
• Symptoms and appearance
• How they spread
• Who gets anogenital warts?
• Diagnosis
• Treatment options
• Prevention
• Psychological impact
• Medical identification codes
• Other names
• Affected body areas

What are anogenital warts?

Anogenital warts are small growths or bumps that appear on the moist tissues of the genital area. They are caused by infection with the human papillomavirus (HPV), which is a family of viruses that infect the skin and mucous membranes^[1]. These warts affect the genitals, the area around the anus, and sometimes other nearby regions.

Anogenital warts are one of the most common types of sexually transmitted infections. Nearly all sexually active people will become infected with at least one type of HPV at some point^[1]. The condition is also referred to by several other medical names, but they all describe the same health issue.

What causes anogenital warts?

About 90% of anogenital warts are caused by HPV types 6 or 11^[2]. These types are called nononcogenic, meaning they do not cause cancer^[2]. There are more than 180 types of HPV that have been identified, and about 35 have an affinity for genital sites^[6].

HPV types 6 and 11 are the two strains that cause genital warts^[3]. These are considered low-risk HPV types because they rarely lead to cancer. However, other HPV types (16, 18, 31, 33, and 35) are occasionally identified in anogenital warts and can be associated with more serious conditions, particularly among people who have HIV infection^[2].

The virus invades cells of the skin’s outer layer after penetrating small breaks in the genital area. After infection, there may be a waiting period of 3 weeks to 9 months before warts appear^[6]. In some cases, warts can appear weeks after sexual contact, but often it takes months or even years^[3].

Symptoms and appearance

Anogenital warts can look different from person to person. They may appear as small, skin-colored bumps or as flat, white patches. Often, the warts are too small to be seen with the eyes alone^[1].

The warts typically have these characteristics:

• Small swellings in the genital area that may be skin-colored or a different color
• A cauliflower-like shape when a few warts grow close together^[1]
• Can be flat, raised (papular), or on a stalk (pedunculated)^[2]
• May feel soft or firm^[5]
• Can be white, red, or darker than the surrounding skin^[5]

Anogenital warts are usually asymptomatic, meaning they don’t cause noticeable symptoms^[2]. However, depending on their size and location, some people may experience:

• Itching or discomfort in the genital area^[1]
• Bleeding during sex^[1]
• Pain, especially if the warts are large^[2]
• Mild bleeding or burning sensation^[3]
• Problems with urination in some cases^[5]

An anogenital wart is typically a flesh-colored growth with a folded, irregular surface measuring a few millimeters across. Warts may join together to form larger areas that can be several centimeters wide^[8].

How they spread

Anogenital warts spread through direct skin-to-skin contact during sexual activity. The virus passes from one person to another when infected skin touches another person’s skin^[3].

Genital warts can spread through:

• Sexual intercourse, including vaginal, anal, or vaginal-to-vaginal contact^[3]
• Genital touching without penetration^[3]
• Oral sex – giving or receiving oral sex with someone who has HPV or genital warts^[3]
• Sharing sex toys^[9]

It’s important to understand that you can have the type of HPV that causes genital warts but never actually develop visible warts. This means you can pass HPV to your partner even without visible symptoms, and they could develop genital warts^[3].

Transmission is more likely from visible warts than from subclinical (not visible) or latent (inactive) HPV infection^[8]. About 2 in every 3 people who have sex with someone infected with genital warts will catch the virus^[9].

The virus can also be transmitted from mother to baby during birth, though this is uncommon. In rare cases, this can lead to warts in the baby’s throat or genital area^[8].

Who gets anogenital warts?

Genital warts can affect anyone who is sexually active. The condition is most common in teenagers and young adults, particularly those in their late teens and 20s^[3]. An estimated 400,000 people get genital warts every year in the United States^[3].

Your chances of getting genital warts increase if you:

• Don’t use condoms or dental dams during sex^[3]
• Have multiple sexual partners^[3]
• Start having sex at a young age
• Smoke cigarettes – smokers are at higher risk of developing genital warts compared to non-smokers^[18]

People whose immune system is weakened are at particular risk. This includes those who have HIV infection or who take medicines that suppress the immune system^[8].

Anogenital warts are rare in people who have been vaccinated against HPV types 6 and 11 before beginning sexual activity^[8]. The use of HPV vaccination has decreased anogenital warts among adolescents, young women, and heterosexual men in multiple countries, including the United States^[2].

Diagnosis

Diagnosis of anogenital warts is usually made by visual inspection during a physical examination^[2]. A doctor or nurse at a sexual health clinic will usually be able to diagnose genital warts just by looking at them^[5].

During an examination, the healthcare provider may:

• Ask about your symptoms and sexual partners^[5]
• Look at the lumps around your genitals and anus, sometimes using a magnifying glass^[5]
• Need to look inside your vagina, anus, or urethra (the tube where urine comes out), depending on where the warts are located^[5]

Visual examination, which may be aided by a magnifying glass, is the only recommended test for routine diagnosis^[4]. HPV testing is not recommended for diagnosing anogenital warts because test results are not confirmatory and do not guide treatment^[2].

A biopsy (removing a small piece of tissue for laboratory examination) is indicated in certain situations^[2]:

• If the diagnosis is uncertain
• If lesions are unusual in appearance (pigmented, hard, fixed to underlying tissue, bleeding, or ulcerated)
• If the patient has a weakened immune system, including those with HIV infection
• If lesions do not respond to standard therapy or worsen during treatment^[2]

Some other conditions can look similar to anogenital warts but require different treatment. These include condyloma lata (a manifestation of secondary syphilis), molluscum contagiosum, and certain types of cancer^[2].

Treatment options

The main goal of treatment is to remove visible warts and relieve symptoms if they are present. The appearance of warts can also cause considerable psychological distress, and removal can relieve cosmetic concerns^[2].

Treatment for genital warts is not always needed. They sometimes disappear on their own within 6 months^[5]. If left untreated, anogenital warts can resolve spontaneously, remain unchanged, or increase in size or number. Because warts might spontaneously resolve in less than 1 year, an acceptable alternative for certain people is to forego treatment and wait for spontaneous resolution^[2].

However, many people want to have them treated because the warts can be uncomfortable or unsightly. Treatment can help speed up the process of clearing the warts. The choice of treatment depends on the number, size, and location of the warts, as well as patient preference, cost, convenience, possible side effects, and the healthcare provider’s experience^[2].

Patient-applied treatments

Some treatments can be applied by patients at home:

• Podofilox (Condyline) solution – recommended for external genital warts on the penis only, as it can irritate skin folds. It should not be used during pregnancy^[18]
• Imiquimod (Aldara) cream – can be used for external genital and perianal warts. It is easy to use and safe when instructions are followed. Not recommended during pregnancy^[18]

These treatments can cause pain, irritation, or a burning sensation. Patients need to follow instructions carefully about how to apply the medicine, as some should only be left on for a certain amount of time before being washed off^[5].

Provider-administered treatments

Other treatments are performed by a healthcare provider:

• Cryotherapy (freezing) – the warts are frozen using liquid nitrogen. This is an excellent first-line treatment, particularly for perianal lesions^[15]. Response rates are high, with clearance occurring in about 75% of cases^[15]. Treatment may need to be repeated several times and can be painful^[5]
• Surgical excision – the warts are cut out after numbing the area with local anesthetic. This has the highest success rate and lowest recurrence rate, with initial cure rates of 63-91%^[15]
• Electrodesiccation – using heat to destroy the warts^[5]
• Laser treatment – using a carbon dioxide laser to remove warts. This is used for extensive or recurrent cases^[15]
• Trichloroacetic acid (TCA) – a chemical applied to the surface of the wart^[18]

These treatments can cause pain, irritation, or scarring in some cases^[5].

It may take weeks or months for treatment to work, and the warts may come back after treatment. Sometimes the treatment does not work^[5]. For most patients, treatment results in resolution of the warts, though available therapies might reduce but probably do not eradicate HPV infectivity^[2].

No definitive evidence indicates that any one recommended treatment is superior to another, and no single treatment is ideal for all patients or all warts^[2]. The cost per successful treatment course is approximately $200 to $300 for podofilox, cryotherapy, electrodesiccation, surgical excision, and laser treatment^[12].

Prevention

There are several ways to reduce your risk of getting or spreading anogenital warts:

HPV vaccination

The most effective way to prevent genital warts is to get the HPV vaccine. Vaccines can help protect against certain strains of HPV that cause most cases of genital warts^[1]. HPV vaccination is highly effective in preventing the development of anogenital warts^[15].

The vaccine is most effective when given before a person becomes sexually active. It is typically recommended for people between the ages of 9 and 26 years^[3]. One vaccine brand protects against four types of HPV, including types 6 and 11 that cause more than 90% of genital warts^[6].

Safe sex practices

• Use condoms correctly every time you have sex. Latex condoms may decrease the risk of contracting genital warts^[18]. However, condoms don’t cover all genital skin, so they may not fully protect against getting HPV^[7]
• Use dental dams during oral sex^[3]
• Limit your number of sexual partners. Having multiple partners increases your risk^[12]
• Be in a mutually monogamous relationship – having sex only with someone who only has sex with you^[7]
• Don’t have sex when you have visible warts, even with a condom, as there may be warts on areas the condom doesn’t cover^[26]

Other preventive measures

• Stop smoking. Research shows that smokers are at higher risk of developing genital warts compared to non-smokers, and warts are more likely to come back if you smoke^[18]
• Talk with your partner or partners about sexually transmitted infections before you have sex^[7]
• Always tell your sexual partners that you have genital warts before you have sex, so you can work together to prevent spreading them^[26]

The only sure way to prevent HPV is to never have oral, anal, or vaginal sex^[7].

Psychological impact

Anogenital warts are essentially a cosmetic problem, but they often cause patients considerable psychological and psychosexual distress^[4]. The appearance of warts can result in considerable psychological distress^[2].

Genital warts can negatively affect health-related quality of life. They may cause anxiety, guilt, anger, and loss of self-esteem. People with genital warts may also experience anxiety about cancer risk^[19].

Anogenital warts can impact psychosexual functioning and quality of life^[8]. Because of these effects, patients are usually highly motivated to have warts detected and removed^[4].

Medical identification codes

A63.0

Other names

Condyloma acuminata, Genital warts, Venereal warts, Condyloma acuminatum, Genital HPV, Genital human papillomavirus infection, Verruca acuminata

Affected body areas

• Vulva
• Vagina (including inside of vagina)
• Cervix
• Penis
• Scrotum
• Anus
• Perianal skin
• Urethra
• Perineum
• Groin area
• Rectum
• Lips
• Mouth
• Tongue
• Throat