What Is a Labial Fusion?

Medically Reviewed by Poonam Sachdev on October 07, 2022
5 min read

A labial fusion, also known as a labial adhesion, occurs when the inner lips (labia minor) of the vagina become sealed together. This condition is most commonly observed in girls under the age of seven, but it can occur at any age. It is not typically a cause of concern. 

It is currently unclear what causes a labial fusion, but physicians have linked it to low estrogen levels in young girls and women. As with other conditions, there are risk factors to be aware of and several treatment options that can facilitate the healing process.

Most cases of labial fusions occur in infants and young girls: These are known as primary labial adhesions. About 2% of female children are affected by labial fusions due to having low levels of estrogen before puberty. These low estrogen levels can also be found in women who have just given birth, as well as those who are experiencing or have already experienced menopause. They can cause what is known as secondary labial adhesion.

Primary labial adhesions are not typically present at birth but will become more apparent when the child is about one or two years of age.

Although there is a link between labial fusions and low estrogen levels, there are also a few other known causes of the actual fusion, or sealing, of the labia in female children and women. 

These causes include:

Skin Irritation

Several different types of skin irritation can contribute to labial fusion. One common skin irritation seen in patients who have primary labial adhesions is diaper rash. Diaper rashes are common in infants, often occurring due to wet diapers that are not changed frequently or to chafing and skin sensitivity. 

The outermost layer of a baby's skin, also known as the stratum corneum, is much thinner than that of adults, making them more susceptible to skin irritation, including inflammation, which significantly contributes to labial fusion. 

Vaginal Infections (Vaginitis)

Vaginitis has also been linked to labial fusions, as it oftentimes accompanies inflammation of the vagina. Vaginitis is caused by an imbalance of the normal levels of yeast and bacteria that live in the vagina. Chemicals in soaps, sprays, and even clothing items can lead to vaginitis, as it disrupts the sensitive balance of the vagina. 

Children and women who have vaginitis will experience itching, burning, redness, swelling, and discharge. It can affect females of all ages and is common in young girls who have not reached puberty, as the outer layer of skin on their vagina is thin and easily irritated. 

Although labial fusions are rare in women who have reached puberty, vaginitis can be one of the primary causes. Once women have reached puberty, their estrogen levels are often balanced, and their vaginal area is further developed and more resistant to skin sensitivities. Vaginitis, however, can still affect women due to things like improper cleaning after using the restroom, sitting in a wet bathing suit, or wearing tight clothing.

After a vaginal delivery, there are often some lacerations in the vaginal area that can also lead to infection. This infection can cause a build-up of fluids that can contribute to distorted anatomical healing, including a labial fusion. This is a rare occurrence, though, and like primary labial adhesions, these cases often heal on their own as the infection is dealt with and the vagina returns to its normal state.


Trauma to the vaginal area can also lead to labial fusions, as trauma often leads to inflammation of the affected area. This trauma can come from injury, childbirth, and repeated sexual friction, including sexual abuse.

Increase in Serum Prolactin

When a woman is breastfeeding, her body often experiences an increase in serum prolactin. This leads to a hypo-estrogenic state in the woman's body, meaning she is experiencing lower levels of estrogen. After childbirth, this lower level of estrogen coupled with edema or trauma to the vaginal area can lead to labial fusions.

The primary symptom seen in cases of labial fusion is a fusion of the vaginal lips. However, some other symptoms may coincide with this, including:

  • Pain when partaking in specific actions that require the spreading of legs (i.e. straddling a bike)
  • Difficulty urinating (in some cases, a complete inability)
  • Urinary tract infection (UTI)
  • Increased vaginal discharge
  • Vulval soreness

Labial fusions often heal on their own with little intervention needed from doctors and medications. However, in more severe cases, treatment may relieve symptoms. 

The two primary labial fusion treatment options that are currently available include:

Oestrogen Topical Cream

Since low estrogen levels are a primary cause of susceptibility to skin irritation and infections in women and children, introducing an estrogen topical cream into your or your child's daily routine may help alleviate labial fusion symptoms. This cream can be applied to the affected area for four to six weeks until the membrane of the labial fusion is dissolved and the vaginal lips are separated. 

Some of the side effects of estrogen creams include irritation, darkening of the skin, and vaginal spotting or bleeding after discontinuing use of the cream. However, these side effects typically disappear shortly and are most often no cause for concern.

Emollients can also take the place of estrogen cream, as they will soothe, hydrate, and cover the vagina with a protective layer. 


In extreme cases, surgery is offered as treatment. This is most often the case in instances where labial fusion is preventing urination or causing infections. The operation is typically easy to complete but is done under either general or local anesthesia, as it can cause discomfort. 

Following the surgery, doctors will suggest the use of an emollient in order to prevent the surgical site from sticking together again.

Labial fusions are not linked to other medical conditions and have not proven to have long-term effects on those who recover. A labial fusion may recur, but the issue is often resolved once a child reaches puberty, and it can be easily prevented in the case of adults. 

Additionally, labial fusions are rare. They are usually not a cause for concern, as they often resolve on their own and can be both easily prevented and treated. In a more severe case, ointments and surgery are offered as treatment options, and emollients can be used to prevent further issues. 

If you or your child are experiencing the symptoms of a labial fusion, speak with your doctor about the specific steps to be taken, preventative actions to take in the future, and treatment options for your case.