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Screening for Bacterial Vaginosis in Pregnant Persons to Prevent Preterm DeliveryUS Preventive Services Task Force Recommendation Statement

Educational Objective
To review the US Preventive Services Task Force (USPSTF) recommendations regarding screening for bacterial vaginosis in pregnant persons to prevent preterm delivery.
1 Credit CME

Importance  Bacterial vaginosis is common and is caused by a disruption of the microbiological environment in the lower genital tract. In the US, reported prevalence of bacterial vaginosis among pregnant women ranges from 5.8% to 19.3% and is higher in some races/ethnicities. Bacterial vaginosis during pregnancy has been associated with adverse obstetrical outcomes including preterm delivery, early miscarriage, postpartum endometritis, and low birth weight.

Objective  To update its 2008 recommendation, the USPSTF commissioned a review of the evidence on the accuracy of screening and the benefits and harms of screening for and treatment of bacterial vaginosis in asymptomatic pregnant persons to prevent preterm delivery.

Population  This recommendation applies to pregnant persons without symptoms of bacterial vaginosis.

Evidence Assessment  The USPSTF concludes with moderate certainty that screening for asymptomatic bacterial vaginosis in pregnant persons not at increased risk for preterm delivery has no net benefit in preventing preterm delivery. The USPSTF concludes that for pregnant persons at increased risk for preterm delivery, the evidence is conflicting and insufficient, and the balance of benefits and harms cannot be determined.

Conclusions and Recommendation  The USPSTF recommends against screening for bacterial vaginosis in pregnant persons not at increased risk for preterm delivery. (D recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for bacterial vaginosis in pregnant persons at increased risk for preterm delivery. (I statement)

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Article Information

Corresponding Author: Douglas K. Owens, MD, MS, Stanford University, 615 Crothers Wy, Encina Commons, Mail Code 6019, Stanford, CA 94305-6006 (

Accepted for Publication: February 21, 2020.

The US Preventive Services Task Force (USPSTF) members: Douglas K. Owens, MD, MS; Karina W. Davidson, PhD, MASc; Alex H. Krist, MD, MPH; Michael J. Barry, MD; Michael Cabana, MD, MA, MPH; Aaron B. Caughey, MD, PhD; Katrina Donahue, MD, MPH; Chyke A. Doubeni, MD, MPH; John W. Epling Jr, MD, MSEd; Martha Kubik, PhD, RN; Gbenga Ogedegbe, MD, MPH; Lori Pbert, PhD; Michael Silverstein, MD, MPH; Melissa A. Simon, MD, MPH; Chien-Wen Tseng, MD, MPH, MSEE; John B. Wong, MD.

Affiliations of The US Preventive Services Task Force (USPSTF) members: Veterans Affairs Palo Alto Health Care System, Palo Alto, California (Owens); Stanford University, Stanford, California (Owens); Feinstein Institute for Medical Research at Northwell Health, Manhasset, New York (Davidson); Fairfax Family Practice Residency, Fairfax, Virginia (Krist); Virginia Commonwealth University, Richmond (Krist); Harvard Medical School, Boston, Massachusetts (Barry); University of California, San Francisco (Cabana); Oregon Health & Science University, Portland (Caughey); University of North Carolina at Chapel Hill (Donahue); Mayo Clinic, Rochester, Minnesota (Doubeni); Virginia Tech Carilion School of Medicine, Roanoke (Epling Jr); Temple University, Philadelphia, Pennsylvania (Kubik); New York University, New York, New York (Ogedegbe); University of Massachusetts Medical School, Worcester (Pbert); Boston University, Boston, Massachusetts (Silverstein); Northwestern University, Evanston, Illinois (Simon); University of Hawaii, Honolulu (Tseng); Pacific Health Research and Education Institute, Honolulu, Hawaii (Tseng); Tufts University School of Medicine, Boston, Massachusetts (Wong).

Author Contributions: Dr Owens had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. The USPSTF members contributed equally to the recommendation statement.

Conflict of Interest Disclosures: Authors followed the policy regarding conflicts of interest described at All members of the USPSTF receive travel reimbursement and an honorarium for participating in USPSTF meetings. Dr Barry reported receiving grants and personal fees from Healthwise.

Funding/Support: The USPSTF is an independent, voluntary body. The US Congress mandates that the Agency for Healthcare Research and Quality (AHRQ) support the operations of the USPSTF.

Role of the Funder/Sponsor: AHRQ staff assisted in the following: development and review of the research plan, commission of the systematic evidence review from an Evidence-based Practice Center, coordination of expert review and public comment of the draft evidence report and draft recommendation statement, and the writing and preparation of the final recommendation statement and its submission for publication. AHRQ staff had no role in the approval of the final recommendation statement or the decision to submit for publication.

Disclaimer: Recommendations made by the USPSTF are independent of the US government. They should not be construed as an official position of AHRQ or the US Department of Health and Human Services.

Additional Contributions: We thank Tina Fan, MD, MPH (AHRQ), who contributed to the writing of the manuscript, and Lisa Nicolella, MA (AHRQ), who assisted with coordination and editing.

Additional Information: The USPSTF makes recommendations about the effectiveness of specific preventive care services for patients without obvious related signs or symptoms. It bases its recommendations on the evidence of both the benefits and harms of the service and an assessment of the balance. The USPSTF does not consider the costs of providing a service in this assessment. The USPSTF recognizes that clinical decisions involve more considerations than evidence alone. Clinicians should understand the evidence but individualize decision-making to the specific patient or situation. Similarly, the USPSTF notes that policy and coverage decisions involve considerations in addition to the evidence of clinical benefits and harms.

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