Title
Prophylactic Antibiotics Did Not Significantly Reduce Infection After Vulvar Surgery, Cohort Study Finds
Highlights
In a prospective single-site cohort of 172 women undergoing vulvar surgery, postoperative infection occurred in 7.6% of cases.
Most infections were observed among patients who had received prophylactic antibiotics, although the study did not show a statistically significant association between antibiotic use and postoperative infection.
The authors concluded that routine prophylactic antibiotics may not meaningfully change short-term outcomes after vulvar surgery and that a randomized controlled trial is needed.
Background
Vulvar surgery is commonly performed for both malignant and premalignant disease, including high-grade vulvar dysplasia and other vulvar lesions that require excision. Because the vulva is anatomically close to the perineum and frequently exposed to moisture, friction, and skin flora, clinicians often worry about postoperative wound infection, wound separation, and delayed healing. These concerns can lead to selective or routine use of perioperative prophylactic antibiotics, even though the evidence base for this practice has been limited.
Antibiotic prophylaxis in surgery is generally intended to reduce surgical site infections by lowering bacterial burden at the time of incision. However, the benefit of prophylaxis depends on the procedure type, contamination risk, tissue perfusion, and baseline infection rate. In procedures with already low infection rates, the absolute benefit may be small, while the harms of unnecessary antibiotics—including adverse drug reactions, Clostridioides difficile infection, antimicrobial resistance, and cost—become more important. That balance makes vulvar surgery an important clinical setting in which to test whether prophylaxis actually improves outcomes.
Study Design
Burns and colleagues conducted a prospective cohort study at a single clinical site involving 12 physicians who performed vulvar surgery. The cohort included women aged 18 years or older who underwent inpatient or outpatient vulvar surgery. Data were collected from electronic medical records and included demographic characteristics, pathologic diagnosis, antibiotic administration, lesion and procedure features, postoperative infection, and other postoperative antibiotic prescriptions.
The primary comparison was between patients who received prophylactic antibiotics at the time of surgery and those who did not. The main endpoint was postoperative infection, assessed at the first postoperative visit. The study also examined overall postoperative complications and potential predictors of complications.
Because this was an observational cohort rather than a randomized trial, antibiotic administration was determined by the treating physicians rather than assigned by protocol. That design reflects real-world practice but also means treatment selection may have been influenced by clinical factors that could affect infection risk.
Key Findings
The final analysis included 172 patients. Prophylactic antibiotics were given to 59.3% of patients (102 of 172). The most common procedure was wide local excision, performed in 58.5% of the cohort (97 patients). The most common pathology among those receiving antibiotics was high-grade dysplasia, reported in 46.1% of treated patients (47 of 102).
Overall, 13 postoperative infections were identified, corresponding to an infection rate of 7.6%. Importantly, 84.6% of these infections (11 of 13) occurred in patients who had received prophylactic antibiotics. On crude analysis, the study found no statistically significant relationship between prophylactic antibiotic use and postoperative infection, with an odds ratio of 4 and a p value of 0.08.
Several points deserve careful interpretation. First, the direction of effect did not favor prophylaxis; if anything, more infections were observed in the antibiotic group. However, this likely reflects confounding by indication: surgeons may have preferentially prescribed antibiotics to patients perceived as being at higher risk because of lesion size, extent of surgery, or other clinical concerns not fully captured in the abstract. In other words, the patients who received antibiotics may have been different at baseline from those who did not.
Second, the small number of infections limits statistical power. With only 13 events, even a clinically meaningful reduction in infection risk could be difficult to detect reliably. The reported odds ratio of 4 with a p value of 0.08 suggests an imprecise estimate rather than definitive evidence of harm or benefit. Confidence intervals were not provided in the abstract, but they would be expected to be wide in a study with so few outcome events.
Third, the study appears to have focused on infection identified at the first postoperative visit. That endpoint is pragmatic and clinically relevant, but it may miss later complications or infections presenting after the initial follow-up window. The abstract also notes that other postoperative complications were not significantly altered by antibiotic use, although detailed complication breakdowns were not provided.
Clinical Interpretation
This study contributes useful real-world evidence to a question that has received relatively little attention: whether routine prophylactic antibiotics improve outcomes after vulvar surgery. Based on the data presented, there is no clear signal that prophylactic antibiotics reduce postoperative infection in this setting.
For clinicians, the finding supports a more selective approach rather than automatic antibiotic administration for every vulvar surgical case. That said, the study does not prove prophylaxis is ineffective in all patients. It suggests that in this cohort, the observed practice of giving antibiotics was not associated with better short-term outcomes. Patients with extensive resection, immunosuppression, diabetes, obesity, prior infection, or other risk factors might still warrant individualized decisions until stronger evidence is available.
The results also raise an important stewardship issue. If routine prophylaxis does not meaningfully lower infection risk, then the potential downsides of unnecessary antibiotic exposure become harder to justify. In gynecologic oncology and vulvar surgery, where patients may already undergo repeated procedures and face complex postoperative care, minimizing avoidable antibiotic use is a reasonable priority.
Strengths and Limitations
A major strength of this study is its prospective design, which generally improves data completeness compared with retrospective chart review. The inclusion of patients from routine practice across 12 physicians also increases clinical relevance and reflects real-world variation in perioperative management.
However, several limitations constrain interpretation. The single-site setting limits generalizability to other institutions, especially those with different case mix, wound care protocols, or surgical techniques. The observational design cannot eliminate confounding by indication. The abstract does not report detailed adjustment for procedure complexity, lesion extent, comorbidities, or surgeon preference, all of which may have influenced both antibiotic use and infection risk. The relatively small sample size and low number of events reduce precision. Finally, postoperative surveillance appears limited to the first follow-up visit, which may underestimate late-onset infection or wound complications.
How This Fits With Current Practice
There are well-established principles for surgical antibiotic prophylaxis in many operations, but vulvar surgery is a less clearly defined area. The current study does not provide sufficient evidence to change practice universally, but it does strengthen the argument that prophylaxis should not be assumed beneficial without procedure-specific evidence.
For gynecologic surgeons, this means perioperative antibiotic decisions should be individualized, taking into account wound class, lesion size, reconstructive complexity, patient comorbidities, and institutional infection rates. A standardized randomized trial would be the best way to determine whether any subgroup derives a measurable benefit from prophylaxis.
Conclusion
In this prospective cohort of women undergoing vulvar surgery, prophylactic antibiotics were not associated with a lower risk of postoperative infection or other short-term complications. The study’s findings do not support routine antibiotic prophylaxis as a clearly effective strategy for all patients, but they do support the need for a randomized controlled trial to clarify which, if any, patients benefit from perioperative antibiotics.
For now, the most defensible approach is cautious, selective antibiotic use guided by individual risk assessment rather than automatic prophylaxis.
Funding and ClinicalTrials.gov
The abstract did not report funding sources or a ClinicalTrials.gov registration number.
References
Burns R, Esposito A, Keomany J, Okut H, Uppendahl L. A comparison of vulvar surgery outcomes after prophylactic antibiotic use. Gynecologic Oncology. 2026-04-15;208:100-105. PMID: 41990444.
Bratzler DW, Dellinger EP, Olsen KM, et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. American Journal of Health-System Pharmacy. 2013;70(3):195-283.
SOGC Clinical Practice Guideline. Antibiotic prophylaxis in gynecologic procedures. Journal of Obstetrics and Gynaecology Canada. 2017;39(1):e1-e10.