{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T08:47:23Z","timestamp":1790844443435,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T00:00:00Z","timestamp":1611100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Introduction: Healthy women of reproductive age have a vaginal pH around 4.5, whereas little is known about pH in the upper genital tract. A shift in the vaginal microbiota may result in an elevated pH in the upper genital tract. This might contribute to decreased fertility and increased risk of preterm birth. Therefore, we aimed to measure pH in different compartments of the female genital tract in both nonpregnant and pregnant women, stratifying into a normal and abnormal vaginal microbiota. Material and methods: In this descriptive study, we included 6 nonpregnant, 12 early-pregnant, and 8 term-pregnant women. A pH gradient was recorded with a flexible pH probe. An abnormal vaginal microbiota was diagnosed by a quantitative polymerase chain reaction technique for Atopobium vaginae; Sneathia sanguinegens; Leptotrichia amnionii; bacterial vaginosis-associated bacterium 1, 2, 3, and TM7; and Prevotella spp. among others. Results: In all participants we found the pH gradient in the lower reproductive canal to be most acidic in the lower vagina and most alkaline in the upper uterine cavity. Women with an abnormal vaginal microbiota had an increased pH in the lower vagina compared to the other groups. Conclusions: There is a pronounced pH gradient within the female genital tract. This gradient is not disrupted in women with an abnormal vaginal microbiota.<\/jats:p>","DOI":"10.3390\/pathogens10020090","type":"journal-article","created":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T12:16:18Z","timestamp":1611144978000},"page":"90","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":54,"title":["Vaginal, Cervical and Uterine pH in Women with Normal and Abnormal Vaginal Microbiota"],"prefix":"10.3390","volume":"10","author":[{"given":"Malene Risager","family":"Lykke","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, Aarhus University Hospital, DK-8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naja","family":"Becher","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology and Genetics, Aarhus University Hospital, DK-8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9304-5299","authenticated-orcid":false,"given":"Thor","family":"Haahr","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Aarhus University Hospital, DK-8200 Aarhus, Denmark"},{"name":"The Fertility Clinic, Skive Regional Hospital Denmark, DK-7800 Skive, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5078-9279","authenticated-orcid":false,"given":"Ebbe","family":"Boedtkjer","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Aarhus University, DK-8000 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7464-7435","authenticated-orcid":false,"given":"J\u00f8rgen Skov","family":"Jensen","sequence":"additional","affiliation":[{"name":"Research Unit for Reproductive Microbiology, Statens Serum Institut, DK-2300 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6449-6426","authenticated-orcid":false,"given":"Niels","family":"Uldbjerg","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Aarhus University Hospital, DK-8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1097\/OGX.0b013e3181e09621","article-title":"Diagnosis and management of bacterial vaginosis and other types of abnormal vaginal bacterial flora: A review","volume":"65","author":"Donders","year":"2010","journal-title":"Obstet. 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