Yeast infection is the type of fungal infection due to any type of Candida (a type of yeast; Pic. 1) that affects the vagina (Pic. 2). The most common type, Candida albicans, naturally lives in the vagina together with bacteria (e.g. Lactobacillus acidophilus; Pic. 3) and is maintained in the natural balance of the vagina. However, this balance can be disrupted under certain circumstances. The yeast can start grow excessively and an infection occur. 

Infection occurs in about 30% of women who are taking a course of antibiotics by mouth. In pregnancy, higher levels of estrogen make a woman more likely to develop a yeast infection. During pregnancy, the Candida fungus is more common, and recurrent infection is also more likely. While infections may occur without sex, a high frequency of intercourse increases the risk. It also seems like synthetic estrogens from hormone replacement therapy and birth control pill may feed Candida.

Signs and symptoms include genital itching, burning, and sometimes a white "cottage cheese-like" discharge from the vagina (Pic. 4). Diagnosis of a yeast infection is done either via microscopic examination or culturing. 

The systemic infections can be life threatening among the individuals having severely paralyzed immune system such as AIDS (Acquired immune system) patients, people undergoing chemotherapy and radiotherapy treatment for cancers, and patients undergoing organ transplants. 

Candida infected patients are commonly treated with a variety of antifungal drugs such as fluconazole, amphotericin B, nystatin, and flucytosine. Moreover, early detection and speciation of the fungal agents will play a crucial role for administering appropriate drugs for antifungal therapy (medication used to treat and prevent mycoses). In pregnancy, there is tentative evidence that treatment of asymptomatic candidal vulvovaginitis reduces the risk of preterm birth.
Recurrent vaginal yeast infection is defined by as having at least 4 episodes or at least 3 episodes not related to antibiotic treatment annually. The causes of repeat vaginal yeast infections in some woman are unknown but some known etiologies of are a type of a Candida strain other than albicans that is resistant to treatment, antibiotics, birth control use, a compromised immune system, sexual activity and hyperglycemia (high blood sugar). Currently, many treatment options available with variable dosage forms (vaginal, oral, cream, etc) and varying dosage frequency ranging from daily treatment to monthly treatments.


Infection of the vagina or vulva may cause severe itching, burning, soreness, irritation, and a whitish or whitish-gray cottage cheese-like discharge. 

Associated diseases

  • HIV infection
  • diabetes mellitus
  • endometriosis (inner lining of the uterus is found in other parts of the body)


Untreated yeast infections can lead to additional health problems, such as infection of bloodstream (candidemia). Repeat infections which reappear right after treatment, or an infection that does not respond to treatment, can be an early sign of diabetes or (in rare cases) HIV.

Many women develop yeast infections during pregnancy because of changes in levels of hormones and pH in the vagina. It is difficult to treat such infections because options for treatment are limited to vaginal creams or suppositories in case of pregnancy. It might take longer — between 10 and 14 days — for a yeast infection to be treated successfully during that time. Normally, a yeast infection should be cured in seven or 14 days. In some cases, Candida could be resistant to treatment (it does not respond to applied drugs). 

A long-term yeast infection can lead to a serious decrease of immune system activity and therefore the chance that the yeast infection can move through the body into its other parts.

Recurrent or severe yeast infections can also interact with menstruation period. Yeast infections can cause production of false estrogen. This then worsens menstrual cramps or causes a disruption to the period.

Risk factors

It is not known exactly how changes in the vagina trigger thrush, but it may be due to a hormone (chemical) imbalance. In most cases, the cause of the hormonal changes is unknown. Some possible risk factors have been identified, such as taking antibiotics.

Antibiotic and steroids

Antibiotic and steroid use is the most common reason for uncontrolled yeast - infection occurs in about 30% of women who are taking a course of oral antibiotics. Antibiotic kills some bacteria, and changes the balance of microorganisms in the body. This may allow the yeast to multiply.

Oral contraceptives

The evidence of the effect of oral contraceptives is controversial.


In pregnancy, changes in the levels of female sex hormones, such as estrogen, make a woman more likely to develop a yeast infection. During pregnancy, the Candida fungus is more prevalent (common), and recurrent infection is also more likely. Moreover, it is harder to treat vaginal yeast during pregnancy and patient can also pass it to a baby during childbirth.

Frequent sexual intercourse

Frequency of sexual intercourse appears to be related to the frequency of infections, however infections often occur without sex. 


Those with poorly controlled diabetes have increased rates of infection while those with well-controlled diabetes do not.

Decreased immunity

The risk of developing thrush is also increased in an immunodeficiency, for example, by an immunosuppressive condition, such as HIV or AIDS, or receiving chemotherapy. This is because in these circumstances the body's immune system, which usually fights off infection, is unable to effectively control the spread of the Candida fungus.


A diet that supports the immune system and is not high in simple carbohydrates contributes to a healthy balance of the oral and intestinal flora. While yeast infections are associated with diabetes, the level of blood sugar control may not affect the risk. 

Wearing cotton underwear may also help to reduce the risk of developing skin and vaginal yeast infections, along with not wearing wet clothes for long periods of time.

Oral hygiene can help prevent oral candidiasis when people have a weakened immune system. For people undergoing cancer treatment, chlorhexidine mouthwash can prevent or reduce thrush. People who use inhaled corticosteroids can reduce the risk of developing oral candidiasis by rinsing the mouth with water or mouthwash after using the inhaler.

It is important that men often don’t have any symptoms but can be carrying the infection and cause repeated infection of their sexual partners. Therefore, they should be treated as well as their female partners. Since it can be passed from person to person, it's always best to practice safe sex by using male or female condoms.

For women who experience recurrent yeast infections, there is limited evidence that oral or intravaginal probiotics help to prevent future infections. This includes either as pills or as yogurt.

If a woman gets yeast infection once or twice a year and it is easily treated, then the only way it will affect fertility is that woman is so uncomfortable from itching and burning that she won’t be in the mood to have sexual intercourse. 

However, yeast infections can change the pH level in the vagina, which can lead to difficulty conceiving. Sperm require a specific pH to survive, and the yeast infection could cause sperm to die before reaching the uterus or fallopian tube. Studies reveal that Candida albicans have sperm-immobilizing property which might lead to infertility.

It has been noted that an imbalance in vaginal flora impairs the vaginal mucosa’s ability to fight off other infections or diseases, which may lead to other fertility issues later in life. 

Candida also affects the lining of uterus and could be linked to endometriosis. Women with vaginal yeast infection are often found to have an immune dysfunction causing an increase in the production of prostaglandin E2, which cause stimulation of the uterine lining (endometrium) and uterine contractions associated with endometriosis. So, Candida makes endometriosis worse.

Yeast infections are highly treatable. Most over-the-counter (OTC) medications generally used for these conditions are available in the form of creams, suppositories, or ovules. They have been shown to be 85 to 95 percent effective in knocking out infections. To work, though, they must be used for the recommended times (usually from three to seven days) and dosages.

Most of the time, symptoms disappear completely with proper treatment. The chances to conceive usually return to a normal state when recurrent yeast infections are finally treated.

Women who have suffered from yeast infections appreciate the convenience of OTC products. But self-treatment with these products can have its drawbacks. For example, if the problem is not a yeast infection, using these products may disrupt the natural vaginal environment, causing irritation and even masking a serious infection. Also, a yeast infection may be confused with more serious bacterial infections or sexually transmitted diseases, which can be aggravated by the use of yeast-infection treatments. For this reason, a first-time sufferer should consult a doctor before undertaking self-treatment. Moreover, if infection recurs, patient should call a doctor before using an OTC treatment.

According to experts, repeated OTC treatment may cause resistance to the medication. If someone is among the 10 percent of women with a yeast infection caused by a resistant species of the Candida organism, his doctor can prescribe some alternative therapies.

Regardless to fertility, having a yeast infection will not directly affect the chances of getting pregnant. But the itchiness and irritation a yeast infection causes probably won't put woman in the mood for intercourse.

Find more about related issues


Candidiasis ―sourced from Wikipedia licensed under CC BY-SA 3.0
A HEALTH GUIDE TO TREATING YEAST INFECTION SAFELY ―sourced from Ground Report licensed under CC BY-NC 4.0
Candida Infections and Their Prevention ―by Kabir and Ahmad licensed under CC BY 3.0
Vaginal yeast infection ―sourced from Wikipedia licensed under CC BY-SA 3.0
Lactobacillus acidophilus ―by AJC1 licensed under CC BY-NC 2.0
C albicans en ―by Y tambe licensed under CC BY-SA 3.0
Speculum exam in candidal vulvovaginitis ―by Häggström licensed under CC0 1.0
Yeast Infection ―by BruceBlaus licensed under CC BY-SA 4.0
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