Yeast infection during pregnancy is an inflammatory lesion of the vaginal mucosa by yeast—like fungi that has arisen or worsened during gestation. It is manifested by curdled vaginal discharge, itching, burning, irritation, vesicular rash in the area of the external genitals, perineum, interstitial and inguinal folds, swelling of the genitals, dyspareunia. It is diagnosed by gynecological examination, microscopic examination of a vaginal smear, PCR, ELISA. For treatment, local antimycotic agents of different groups are used — polyenes, azoles, combined drugs.
Yeast infection during pregnancy (vaginal candidiasis, candidiasis vaginitis) at least once in a lifetime, it occurs in more than 2/3 of women of reproductive age, in 40-50% of cases, episodes of the disease are repeated, and in 5% of patients, the infection takes a chronic recurrent course. Colpitis caused by yeast-like fungi is diagnosed in 30-40% of pregnant women, which is 2-3 times more common than in non-pregnant women. Before childbirth, its frequency reaches 44.4%. The wide prevalence of thrush is explained by the presence of yeast-like fungi as part of the natural microcenosis of the vagina in 10-17% of women before pregnancy and prolonged asymptomatic candidiasis. The infection affects urban women more often and is more common in countries with hot climates.
Up to 90-95% of cases of yeast infection during pregnancy caused by conditionally pathogenic undisputed yeast-like fungi Candida albicans (C. Albicans). In recent years, there has been an increase in the number of colpites, in which other candide species are sown from the secretions — C. kefyr, C. krusei, C. guilliermondii, C. tropicalis, etc. A dangerous pathogen of nosocomial infections is Candida glabrata. Normally, yeast-like fungi in the form of single inactive rounded cells that do not form mycelium filaments are present in the microflora of 80% of pregnant women, but their growth is restrained by vaginal lactobacilli (Doderlein sticks), with which candida are in a competitive relationship.
Although candidiasis can be transmitted sexually from an infected partner, usually a key factor in the occurrence of the disease is a violation of immunity and a decrease in the number of lactobacilli. The risk of developing thrush increases in the presence of chronic somatic pathologies, diabetes mellitus, hypothyroidism, hypoparathyroidism, hypercorticism, severe general diseases (leukemia, lymphoma, HIV infection, etc.), uncontrolled use of antibiotics, glucocorticoids, cytostatics, intestinal dysbiosis, hypovitaminosis, chronic stress and emotional stress, climate change.
Predisposing factors are the use of daily pads that increase the humidity of the genitals due to the violation of air access, wearing tight underwear made of synthetic fabrics, obesity, eating a large number of sweets and carbohydrate dishes. The clinical manifestation of thrush during pregnancy is also promoted by:
- Accumulation of glycogen in the vaginal mucosa. Under the action of estrogens, the number of epithelial cells containing glycogen increases. With a decrease in the number of lactobacilli that break down glycogen to lactic acid, it becomes a suitable breeding ground for candida.
- A natural decrease in immunity. In pregnant women, under the influence of high concentrations of progesterone, corticosteroids and immunosuppressive factor associated with globulins, immunity decreases. This prevents the rejection of the fetus as a foreign body by the maternal body and supports gestation.
With yeast infection during pregnancy, the infectious process is first localized in the surface layers of the mucosa. At the stage of adhesion, candida attach to epithelial cells and colonize the vagina, after which they are embedded in epithelial cells. After invasion, multipolar budding of microorganisms begins with their transformation into thin filamentous forms (pseudomycelia). If a woman’s body can restrain their growth, but is not able to completely eliminate the pathogen due to insufficient cytokine effect and low interferon G levels, fungi persist at this level for a long time without affecting the deeper layers of the mucosa.
With a decrease in immunity, the pathogen passes the epithelial barrier, penetrates the connective tissue and actively grows, overcoming cellular and tissue defense mechanisms. The ingress of candide into the vascular bed contributes to hematogenic dissemination with damage to other organs and systems. The upward spread of fungi is dangerous for the child – in the third trimester, the antimicrobial activity of amniotic fluid is quite low, so the causative agent of candidiasis multiplies well in them. When mushrooms come into contact with mucous membranes and skin, ingestion and aspiration of infected waters, infection of the fetus occurs.
The systematization of clinical forms of thrush during pregnancy is based on such key criteria as the severity of symptoms, the peculiarity of the course of the infectious process and the association of candida with other pathogens of urogenital infections. In most pregnant women, vaginal candidiasis is either asymptomatic or prone to frequent recurrence. The true primary acute process is rarely observed. In obstetrics , the following variants of thrush are usually diagnosed:
- Asymptomatic candidacy. There are no clinical symptoms. The titer of fungi in the vaginal microcenosis does not exceed 104 CFU/ml. Bacterial examination of vaginal secretions is dominated by lactobacilli, determined in moderate amounts.
- True candidiasis. There is a typical clinical picture of thrush. The candide titer is greater than 104 CFU/ml, lactobacilli with a high titer (over 106 CFU/ml) are detected. Diagnostically significant titers of other opportunistic agents are not detected.
- A combination of candidiasis and bacterial vaginosis. Polymicrobial associations are sown from the vaginal secretions. In addition to the high titer of mushrooms in large quantities (over 109 CFU / ml), obligate anaerobes and gardnerella are determined. Lactobacilli are few or absent.
With an asymptomatic carrier, a woman usually does not make any complaints. The most characteristic manifestation of manifested candidiasis is moderate or abundant curd vaginal discharge and white plaque on the genitals, consisting of candida mycelium, leukocytes and damaged epithelial cells. With thrush, irritation, itching, burning in the genital area are often noted, increasing at night, after hygienic procedures or sexual intercourse. There may be an unpleasant odor from the genitals. Due to increased blood circulation in the vaginal mucosa, the genitals swell.
When the vestibule of the vagina, labia minora and labia majora are involved in the inflammatory process, burgundy vesicles with liquid contents form on their surface, after opening which microerosions and crusts form. In overweight patients, the rash can spread to the skin of the perineum, inguinal and interstitial folds. Due to the increased sensitivity of the inflamed vaginal mucosa, a pregnant woman with thrush experiences discomfort and pain during sexual intercourse. The penetration of fungi into the urinary system is indicated by increased urination and the appearance of cuts. The upward spread and generalization of the infection are manifested by aching pains in the lower abdomen, an increase in temperature.
Pregnant women suffering from thrush are more likely to have a threat of termination of pregnancy, the risk of spontaneous abortions and premature birth increases. With the upward spread of the infectious process to the mucous membrane of the cervix, endocervicitis develops, damage to the fetal membranes leads to chorioamnionitis, untimely outflow or leakage of amniotic fluid, chronic hypoxia, intrauterine infection of the fetus with signs of its hypotrophy. During childbirth, the probability of ruptures of inflamed soft tissues increases. Typical complications of the postpartum period are endometritis, wound infection of the birth canal, subinvolution of the uterus. The frequency of intrauterine, intra- and postnatal infection with yeast-like fungi in children has increased from 1.9% to 15.6% over the past 20 years. In approximately 10% of cases of fetal and newborn deaths, changes characteristic of candidiasis are detected.
With a typical clinical picture, the diagnosis of thrush in a pregnant woman is not particularly difficult. A more thorough diagnostic search is required if a carrier or subclinical course of the disease is suspected. Due to the presence of a small number of fungi in the natural microcenosis of the vagina, sowing for candida is used only limited, mainly to determine the sensitivity of the pathogen and control the effectiveness of treatment. The most informative survey methods are:
- Examination on the chair. Examination in mirrors reveals hyperemia of the mucous membrane, the presence of white plaque on its surface. Abundant curd discharge from the vagina is characteristic. A vesicular rash may be found on the external genitals of a pregnant woman, spreading to the perineum and natural folds of the skin.
- Smear on flora in women. Unpainted or stained smears obtained from the urethra, cervical canal and vagina are examined under a microscope. With candidiasis, single budding cells of yeast-like fungi, pseudomycelia, blastoconidia, pseudogypha, and other morphological structures are determined in the preparation.
PCR diagnostics of yeast infection during pregnancy, ELISA (determination of antibodies to candida) can be recommended as auxiliary methods for thrush. The methods are highly sensitive and specific, but, like sowing, they are used only to a limited extent due to the presence of the pathogen in the natural vaginal microflora. Differential diagnosis is carried out with other infectious and inflammatory diseases of the vagina – bacterial vaginosis, genital herpes, nonspecific bacterial and trichomonas vulvovaginitis, chlamydia, gonococcal, bacterial exo- and endocervicitis. If necessary, the patient is consulted by an infectious disease specialist, a dermatologist, a venereologist, a urologist.
Treatment of yeast infection during pregnancy
The main task of yeast infection during pregnancy is the complete elimination of the pathogen with the help of highly effective, well-tolerated, non-toxic drugs for the fetus and woman. Local application of antimycotic agents in the form of vaginal candles is preferable, when using which symptoms are eliminated more quickly, minimal systemic absorption of active substances is noted. Yeast infection during pregnancy are recommended:
- Polyene antimycotics. Fungicidal antibiotics cause the death of yeast-like fungi due to the formation of numerous channels in the candide membranes and the destruction of microorganisms due to uncontrolled loss of electrolytes. Antibiotics from the polyene group are characterized by low resorptivity and are practically not absorbed by the mucous membranes, which is especially important for pregnant women.
- Azoles (imidazoles, triazoles). The fungistatic effect of azole agents is based on the suppression of the synthesis of ergosterol of the cell membrane. Since sterols are synthesized in this way only in fungi, the drugs practically do not affect the enzyme that catalyzes the production of cholesterol in humans. Due to the possible teratogenic effect of systemic azoles, local forms are prescribed.
- Combined drugs. The composition of such drugs contains several imidazole antimycotics or, in addition to polyenes, there are other antibiotics — aminoglycosides, polypeptides, etc. The appointment of combined medications is justified when thrush is combined with bacterial vaginosis and in therapeutically resistant cases with a high risk of complications.
Despite its high effectiveness, echinocandins with embryotoxic effect and allylamines are not used in the treatment of candidiasis in pregnant women. The so-called drugs of different groups are used only to a limited extent, taking into account possible effects on the fetus. Active outpatient treatment of thrush is carried out at the stage of prenatal preparation to exclude intranatal infection of the fetus. If the partner of a patient with candidiasis shows signs of candidiasis balanoposthitis, he is also prescribed antimycotics. In the absence of obstetric contraindications, a pregnant woman is shown natural childbirth.
Prognosis and prevention
With the timely appointment of antimycotic agents and the absence of severe forms of immunosuppression, the prognosis for the woman and child is favorable. Prevention includes strengthening the immune system, wearing comfortable underwear made of natural fabrics, observing the rules of personal hygiene with washing with intimate gels containing lactic acid. Pregnant women who had a recurrent course of thrush before gestation are recommended early registration with an obstetrician-gynecologist, sufficient rest, exclusion of stress loads, correction of diet with an increase in the amount of fermented dairy products, fruits, vegetables in the diet.