BackgroundHaemophilus influenzae(Hi) is an emerging cause of early onset neonatal sepsis, but mechanisms of transmission are not well understood. We aimed to determine the prevalence of vaginal carriage ofHiin reproductive age women and to examine behavioral and demographic characteristics associated with its carriage.MethodsWe performed a secondary analysis of stored vaginal lavage specimens from a prospective cohort study of nonpregnant reproductive-age women. After extraction of bacterial genomic DNA, samples were tested for the presence of the gene encodingHaemophilusprotein d (hpd) by quantitative real-time polymerase chain reaction (PCR) using validated primers and probe. PCR for the V3-V4 region of the 16 S rRNA gene (positive control) assessed sample quality. Samples with cycle threshold (CT) value < 35 were defined as positive. Sanger sequencing confirmed the presence ofhpd. Behavioral and demographic characteristics associated with vaginal carriage ofHiwere examined.Results415 samples were available. 315 (75.9%) had sufficient bacterial DNA and were included. 14 (4.4%) were positive forhpd. There were no demographic or behavioral differences between the women withHivaginal carriage and those without. There was no difference in history of bacterial vaginosis, vaginal microbiome community state type, or presence of Group BStreptococcusin women with and without vaginal carriage ofHi.ConclusionHiwas present in vaginal lavage specimens of 4.4% of this cohort.Hipresence was unrelated to clinical or demographic characteristics, though the relatively small number of positive samples may have limited power to detect such differences.