Risk score for antenatal bacterial vaginosis: BV PIN points.
OBJECTIVE
Develop a clinical risk score to screen for antenatal bacterial vaginosis (BV), irrespective of symptoms.


METHODS
Cohort study of 913 pregnant women with last menstrual periods between January 30, 1995 and February 22, 1997. BV was evaluated by Nugent-scored vaginal smears (scores of 7 to 10 considered positive) between 24 and 29 weeks' gestation. Forty-four potential risk factors were assessed.


RESULTS
17.8% of women had BV, of whom 22% were screened for BV by the usual care provider. Logistic regression-adjusted analyses found six predictors: vaginal pH>4.5 (OR=11.6, 95% confidence interval [CI] [7.8, 17.2]); black race (OR=1.9, 95% CI [1.3, 2.8]); condom use during pregnancy (OR=1.6, 95% CI [1.0, 2.5]); antenatal BV (OR=1.7, 95% CI [1.0, 2.8]); absence of sperm on smear (OR=1.7, 95% CI [1.0, 2.9]); and no history of sexually transmitted diseases (OR=1.6, 95% CI [1.0, 2.5]). Risk score weights were 5 for an elevated vaginal pH and 1 otherwise. The sensitivity and specificity of screening women with scores > or =4 were both 77%; this would involve screening 33% of patients.


CONCLUSIONS
Approximately 80% of our BV cases were asymptomatic, emphasizing the need for objective risk assessment. Using six factors, clinicians can identify pregnant women at risk for BV.
Pastore
Lisa M
LM
Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill, NC 27517-9212, USA.
Thorp
John M
JM
Royce
Rachel A
RA
Savitz
David A
DA
Jackson
Tracy P
TP
D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005865:Gestational Age; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D016017:Odds Ratio; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000453:epidemiology*; D011256:Pregnancy Outcome; D012307:Risk Factors; D014626:Vaginal Smears; D016585:Vaginosis, Bacterial / Q000175:diagnosis / Q000453:epidemiology*