Causes and risk factors of yeast infection


Candida is the organism responsible for yeast infections , but it usually lives in the vagina in balance with bacteria without causing any problems. Changes in vaginal acidity and body balance can be due to antibiotics, diabetes, pregnancy, hormone therapy, birth control, or a compromised immune system. When this happens, Candida cells can proliferate uncontrollably, leading to a yeast infection.

© Get Information on Medicines, 2018

Common causes

Yeast infections have multiple causes, and some people may have more than one when infection occurs.

Antibiotic treatment

This is a common cause of yeast infections . Lactobacilli , which are generally found in the vagina, produce substances and levels of acidity that inhibit yeast. Antibiotics kill some of these beneficial bacteria, allowing yeast to grow.

Estrogen surge

Elevated estrogen levels increase the risk of a yeast infection. Pregnant women, women taking high-dose estrogen birth control pills, and women receiving hormone replacement therapy are at higher risk than others.


If your immune system is weakened by the use of corticosteroids, cancer treatments, HIV infection, or other reasons, you are at increased risk for yeast infections.


You are especially prone to vaginal yeast infections if you have diabetes. The yeast cells that normally live in the vagina are carefully controlled for the minimal nutrients available in the acidic environment of the vagina. However, in women and girls with diabetes, the vaginal discharge contains more glucose due to the higher amount of glucose in the blood. Yeast cells feed on this excess glucose, causing them to proliferate and turn into a yeast infection.

High blood sugar also interferes with immune functions, which help prevent yeast infections. The presence in women with diabetes may indicate that blood glucose levels are poorly controlled or that an infection is developing in another part of the body.

The mere presence of yeast also blocks the body's natural defenses against other infections, increasing your risk in people with diabetes. Any infection in a person with diabetes is a risk because blood sugar levels can be much higher or lower than normal as the body tries to defend itself.

If you suffer from four or more yeast infections per year, ask your doctor to make sure your diabetes is adequately controlled.

Cancer treatment

Vaginal yeast infection is often considered a side effect of cancer treatments. The white blood cells that normally keep the yeast normally present in the vagina and digestive tract from overgrowth can be reduced with chemotherapy and radiation therapy. Steroid medications can also lower your immune system's ability to maintain balance. High-dose antibiotics, sometimes used to treat cancer, can also cause yeast infections.

Sexual activity

Yeast infections occur without sexual activity and therefore are not considered sexually transmitted infections (STIs). However, yeast can be passed between sexual partners through vaginal, oral, or anal sex. You can use a condom or tooth pad to protect against this. If your sexual activity irritates the vagina, it can upset the normal balance and cause yeast overgrowth.

Male sexual partners of a woman who has a yeast infection can develop a yeast rash on the tip of the penis . A man is at higher risk if he has diabetes. A medical examination and treatment is required.

Lifestyle risk factors

You can change habits or practices that increase your risk of vaginal yeast infection. Follow these tips to reduce heat, humidity, irritation, and other risk factors.

  • What you wear can make a difference. Cotton crotch underwear is recommended, not synthetic fabric. Baggy skirts and pants will help keep you cool and dry. Avoid wearing tight leggings and pants that are snug at the crotch. Change out of wet or damp clothing, including bathing suits and sportswear, as soon as possible.
  • Change your tampon , pad, or panty liner often.
  • Do not take a shower , as this will kill the beneficial bacteria and change the acidity of the vagina.
  • After you have a bowel movement, wipe it from front to back to avoid getting yeast out of your stool.
  • Feminine fragrances, bath products, and sprays can irritate the vaginal area and should be avoided.
  • Use a vaginal lubricant during intercourse to prevent irritation. You can also use a condom or tooth pad to prevent yeast from passing between you and your partner.
  • Avoid very hot baths and hot tubs.
  • If you have diabetes, try to keep your blood sugar in good control.

When treating a yeast infection , especially if you have diabetes, take all the medicines your doctor recommends. If you stop taking the medicine sooner because you feel better or if your symptoms have gone away, the infection may come back and get worse than before.

Frequently asked questions

  • Yeast infections are caused by the Candida fungus. The vast majority of yeast infections are caused by Candida albicans ( C. albicans ) . Less common types include C. parapsilosis, C. dubliniensis, and C. auris, which are more common in people with weakened immune systems and severe systemic infections .

  • Candida albicans generally lives in the body without causing problems, but it can grow suddenly when the immune system weakens or the vaginal environment changes. Risk factors include:

    • Use of antibiotics
    • Chemotherapy
    • HIV infection
    • Hormonal contraceptives
    • Poorly controlled diabetes
    • The pregnancy

  • Genital hygiene alone is not considered a risk factor for yeast infection. However, poor personal hygiene combined with a high frequency of sexual intercourse increases the likelihood of transmission of the fungus from one sexual partner to another.

  • An uncircumcised penis is one of the main risk factors. This is because the moist environment under the foreskin encourages the growth of Candida . Poor penis hygiene and obesity further increase the risk.

Related Articles
Foods to Avoid If You Have Dry Mouth From Radiation

Dry mouth (xerostomia) is a common side effect of radiation therapy for people undergoing treatment for head and neck cancer. Read more

Thyroid adenoma: Causes, Treatment, and Diagnosis

The thyroid is a small, butterfly-shaped gland in the front of your throat that produces hormones affecting a number of Read more

NSAIDs and You Thyroid Function

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most frequently taken over-the-counter medications. Due to their systemic or whole body effects, it's Read more

How Doctors Are Failing Thyroid Disease Patients

The thyroid disease community has continually mentioned the lack of support they experience and the difficulty they have navigating the Read more