Can vaginal candida fungus cause negative pregnancy outcomes?

Vaginal fungus Candida albicans

Vaginal mycosis can be caused by an imbalance of the vaginal flora. This involves the spread of yeast fungi such as Candida albicans, Candida glabrata or Candida tropicalis in the genital tract. Studies suggest that these infections may be a risk factor for preterm birth and possible fetal growth restriction (FWR).

In addition to the usual symptoms of Candida fungi such as itching or vaginal discharge, such infestations may also manifest asymptomatically. However, data identifying such a yeast infection as a direct cause of adverse pregnancy outcomes are partially contradictory. On the one hand, observational results exist that clarify that preterm births are not affected by vaginal Candida fungal disease. On the other hand, a meta-analysis showed that medical treatment of asymptomatic vaginal Candida disease in 685 pregnant women could reduce the risk of spontaneous preterm birth.

The current meta-analysis by researchers from the USA aims to use the observational data examined to provide an overview of the association between vaginal yeast Candida in pregnant women and adverse pregnancies. The background for this was the lack of available data on whether or how much an asymptomatic vaginal yeast infection increases or influences the risk of preterm birth or disadvantages for delivery.

Meta-analysis

This meta-analysis was conducted using the 2020 Guidelines for Analysis of Observational Studies"Preferred Reporting Items for Systematic Reviews andMeta-analyses" and"Meta-analyses of Observational Studies in Epidemiology". For this, published data and studies from Ovid MEDLINE, Ovid Embase, and the Cochrane Central Register of Controlled Trials on vaginal candida or yeast fungus and pregnancy outcomes were examined within this time frame.

The criteria for each of the studies analyzed were: Cohort studies, case-control studies, and randomized controlled trials that recorded pregnant women who were evaluated for asymptomatic expression of incident Candida and documented adverse pregnancy outcomes.
Zwei unparteiische Gutachter wählten und filterten die Daten aus. Anhang von bestimmten Bewertungsskalen (z.B.: Newcastle-Ottawa Quality Assessment Scale) wurden die einzelnen Kohortenstudien und Fall-Kontroll-Studien ausgewertet – die randomisierten, kontrollierten Studien analysierte man mithilfe des Cochrane Risk-of-Bias-Tools.

Is there a link?

Researchers of the meta-analysis published in 2020 in the American Journal of Obstetrics and Gynecology - Maternal Fetal Medicine included data from 15 studies involving 33,321 women. The study found no significant difference in preterm birth rates (whether spontaneous preterm birth or not) between women with Candida and women without Candida. The odds ratio for untreated women with Candida was increased in 3 studies with a total of 5175 study participants. Nevertheless, the researchers report that a subgroup analysis for treatment of vaginal candida failed to show a significant association in women with spontaneous preterm birth. Also, asymptomatic vaginal vaginal thrush (with Candida) showed no association with preterm birth, prenatal mortality, or other adverse pregnancy outcomes.

Conclusion

Overall, according to the meta-analysis, no association was found between asymptomatic vaginal Candida disease and adverse pregnancy outcomes. Additionally, no association with spontaneous preterm birth was recorded among analysis participants, regardless of the type of treatment. Unlike previous research that found an association between treatment for vaginal yeast infections and a reduction in the risk of preterm birth, the current evaluations suggest that this effect may not be correlated with treatment for vaginal candida fungus. Nevertheless, this study is not a substitute for professional medical evaluation by a physician - in the case of an asymptomatic (and especially symptomatic) vaginal candida case during pregnancy, you should consult with your treating physician.