What are the implications of asymptomatic Candida (fungal infection) in pregnancy?

From the Guidelines

Asymptomatic candida colonization during pregnancy does not require treatment, and a watchful waiting approach is recommended. This approach is based on the most recent evidence from the 2022 review of vulvovaginal candidiasis for the Centers for Disease Control and Prevention of Sexually Transmitted Infections treatment guidelines 1. If candida is detected in vaginal or urine cultures but the patient has no symptoms such as itching, burning, or abnormal discharge, treatment is not indicated unless symptoms develop or in specific situations like prior to certain obstetric procedures.

Key Considerations

• The reason for this conservative approach is that candida can be part of the normal vaginal flora in up to 20-30% of pregnant women, and asymptomatic colonization rarely leads to complications, as noted in the 2002 guidelines for sexually transmitted diseases treatment 1.
• However, pregnant women should be advised to report any symptoms that develop, as hormonal changes during pregnancy can increase susceptibility to symptomatic infections.
• Good hygiene practices, wearing cotton underwear, and avoiding douches or scented products can help prevent symptomatic infection from developing.

Treatment Approach

• If treatment becomes necessary, topical azole medications such as clotrimazole or miconazole are preferred during pregnancy and are typically used for 7 days.
• Oral fluconazole should be avoided, especially in the first trimester, due to potential risks to the fetus. The most recent and highest quality study, the 2022 review 1, supports this approach, emphasizing the importance of evidence-based treatment guidelines for vulvovaginal candidiasis, including considerations for pregnancy.

From the FDA Drug Label

Potential for Fetal Harm: Use in pregnancy should be avoided except in patients with severe or potentially life-threatening fungal infections in whom fluconazole may be used if the anticipated benefit outweighs the possible risk to the fetus A few published case reports describe a pattern of distinct congenital anomalies in infants exposed in utero to high dose maternal fluconazole (400 to 800 mg/day) during most or all of the first trimester. Epidemiological studies suggest a potential risk of spontaneous abortion and congenital abnormalities in infants whose mothers were treated with 150 mg of fluconazole as a single or repeated dose in the first trimester, but these epidemiological studies have limitations and these findings have not been confirmed in controlled clinical trials

The use of fluconazole in pregnant women with asymptomatic candida is not recommended, as the potential risk to the fetus may outweigh the benefits of treatment, except in cases of severe or potentially life-threatening fungal infections.

• Severe fungal infections: Fluconazole may be used if the anticipated benefit outweighs the possible risk to the fetus.
• Asymptomatic candida: The FDA drug label does not provide guidance on the use of fluconazole for asymptomatic candida in pregnancy, and the potential risks and benefits of treatment should be carefully considered on a case-by-case basis 2 2.

From the Research

Asymptomatic Candida in Pregnancy

• Asymptomatic vaginal colonization with Candida albicans in early pregnancy is associated with preterm delivery and low birthweight, as found in a study of 8447 women with singleton pregnancies 3.
• The prevalence of vulvovaginal candidiasis (VVC) during pregnancy is estimated to be around 20%, peaking at about 30% in the third trimester, with specific risk factors predisposing to yeast infection 4.
• Candida species may be present in the vaginal flora of up to 40% of healthy pregnant women, and while candidiasis is not usually associated with chorioamnionitis or preterm delivery, there is some emerging evidence to suggest that screening for and eradication of candida during pregnancy may reduce the risk of preterm delivery 5.

Treatment of Asymptomatic Candida in Pregnancy

• Vaginal nystatin and oral fluconazole are effective treatments for recurrent vulvovaginal candidiasis (RVVC), with similar mycological cure rates 6.
• Miconazole nitrate administered intravaginally has been found to achieve comparable therapeutic and mycological cure rates in both pregnant and nonpregnant women, and is significantly better than nystatin, clotrimazole, and butoconazole in treating vaginal candidiasis during gestation 7.
• Routine screening and consequent treatment for candidiasis could improve pregnancy outcomes, particularly in cases of recurrent asymptomatic vaginal colonization with Candida in early pregnancy 3.

Risk Factors and Outcomes

• The hyperestrogenic environment of the vaginal mucosa and reduced immune defenses during pregnancy create conditions favorable for Candida spp. vaginal colonization and hence VVC 4.
• Recent evidence shows an association between VVC and adverse obstetric outcomes, including premature membrane rupture (PROM), chorioamnionitis, preterm birth, and puerperal infections 4.
• Recurrent asymptomatic vaginal colonization with Candida in early pregnancy is associated with higher rates of preterm delivery and low birthweight, as confirmed in a multiple model analysis 3.