In a landmark announcement on July 30, 2026, Quest Diagnostics Inc. (NYSE: DGX) revealed the results of a comprehensive Health Trends® study that highlights a concerning correlation between bacterial vaginosis (BV) and the likelihood of co-infection with sexually transmitted infections (STIs). This study, conducted in collaboration with Hologic, Inc., analyzed deidentified laboratory data from over 1.5 million women across the United States who underwent molecular testing between 2022 and 2024.

The findings, published in the peer-reviewed journal *O&G Open*, indicate that women testing positive for BV are more than three times as likely to also test positive for one or more non-viral STIs compared to those who test negative for BV. This significant revelation marks the largest national study of its kind and sheds light on the urgent need for further research in women's health.

2. Alarmingly High Prevalence of Bacterial Vaginosis

According to the study, 38.7% of the women tested positive for BV, while 28.5% were found to have vulvovaginal candidiasis, with approximately 10.8% of the participants exhibiting both conditions. Alarmingly, 12% of those with BV were co-infected with at least one STI, a stark contrast to the 3.8% of women without BV who tested positive for STIs.

Dr. Damian P. Alagia III, co-author of the study and Senior Medical Director of Women's Health at Quest Diagnostics, emphasized the significance of these findings. “BV is one of the most common health problems in women, and yet research in this area of women's healthcare is sadly lacking. Our new analysis provides compelling evidence that women with BV are at significant risk for STIs,” he stated.

3. A Closer Look at STI Risks

The study further indicates that women with BV face heightened odds of specific STIs. After adjusting for confounding factors, the odds of testing positive for various infections were substantially increased as follows:

Chlamydia trachomatis: 2.8 times higher odds

Neisseria gonorrhoeae: 3.8 times higher odds

Trichomonas vaginalis: 3.6 times higher odds

Mycoplasma genitalium: 1.9 times higher odds

Interestingly, the presence of vulvovaginal candidiasis alone did not correlate with an increased risk of STI co-infection, suggesting that BV plays a unique and critical role in this health dilemma.

4. Implications for Women's Health and Healthcare Policy

This study underscores the importance of comprehensive diagnostic approaches for women presenting with symptoms of BV, as STIs can lead to serious reproductive health complications when left undiagnosed and untreated. The Centers for Disease Control and Prevention (CDC) recommends STI testing for women diagnosed with BV, due to the overlapping symptoms that can complicate proper diagnosis.

Elizabeth M. Marlowe, MS, PhD, Executive Director of Infectious Disease at Quest Diagnostics, remarked, “This research confirms and expands on previous research on increased STI risk in women with BV, but with the advantage of a much larger data set from which to draw conclusions.”

5. The Future of Testing and Diagnosis

In response to the study's findings, Quest Diagnostics has continued to innovate in the realm of women's health. In 2024, the company introduced self-collection services for bacterial vaginitis and other common genital tract infections at its extensive network of over 2,000 patient service centers, allowing women the option to collect specimens privately.

The study's robust design, featuring a diverse and nationally representative sample, strengthens the evidence-base for clinical guidelines emphasizing the necessity of advanced molecular testing. However, it is important to note that the study was retrospective and based on data from a single national laboratory, limiting some aspects of patient-specific information.

6. Conclusion

The findings from Quest Diagnostics not only illuminate the significant health risks associated with bacterial vaginosis but also highlight the critical need for enhanced research and comprehensive diagnostic practices in women's healthcare. With nearly 30% of women in the U.S. believed to experience BV at some point in their lives, these insights pave the way for better prevention and management strategies that could significantly improve women's health outcomes.

As Quest Diagnostics continues to lead the charge in diagnostics, the implications of this study may very well resonate throughout the healthcare landscape, prompting a reevaluation of current practices and policies regarding women's health.

Original press release