{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:19:04Z","timestamp":1760231944439,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T00:00:00Z","timestamp":1650931200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>The aim of this trial was to evaluate the effect of progesterone gel compared to placebo in prolonging pregnancy among women with preterm labor. Methods: A randomized controlled trial in Sweden in 2009\u201318. Women with early preterm labor were randomized to daily doses of progesterone gel 90 mg (n = 28) or placebo (n = 30) after standard intravenous tocolytics. Women with intravenous tocolytics alone (n = 29) served as controls. Results: The median latency to delivery was 68 (range 28\u201388) days with progesterone and 72 (range 9\u201390) days with placebo (p = 0.84), compared to 1 (range 1\u20132) day in the control group (progesterone and placebo vs. control p &lt; 0.001). The rate of preterm birth before 34 weeks was 32% after progesterone and 37 % after placebo (p = 0.32) compared to 100 % in the control group (p &lt; 0.001, respectively). The composite neonatal morbidity (p = 0.65) and neonatal intensive care unit admission (p = 0.12) were comparable between the progesterone and placebo groups and lower in these groups compared with neonates in the control group (p &lt; 0.001, respectively). Conclusions: Progesterone gel and placebo were equally effective in prolonging pregnancy among women with early preterm labor, and both treatments were more effective than standard intravenous tocolysis alone. We hypothesize that the acidic placebo gel reinforced the biochemical barrier at the uterine cervix, which counteracts ascending pathogen invasion and subsequent inflammation, and thereby prevented preterm labor.<\/jats:p>","DOI":"10.3390\/gels8050272","type":"journal-article","created":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T11:45:55Z","timestamp":1650973555000},"page":"272","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Progesterone Gel and Placebo Prolonged Pregnancy More Effectively Than Intravenous Tocolysis Alone in Women with Preterm Labor"],"prefix":"10.3390","volume":"8","author":[{"given":"Ylva","family":"Vladic Stjernholm","sequence":"first","affiliation":[{"name":"Department of Women\u2019s and Children\u2019s Health, Karolinska University Hospital and Karolinska Institutet, Akademiska Str\u00e5ket 14, 171 64 Stockholm, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomislav","family":"Vladic","sequence":"additional","affiliation":[{"name":"Department of Women\u2019s and Children\u2019s Health, Karolinska University Hospital and Karolinska Institutet, Akademiska Str\u00e5ket 14, 171 64 Stockholm, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Giovanna","family":"Marchini","sequence":"additional","affiliation":[{"name":"Neonatal Unit, Astrid Lindgren\u2019s Children\u2019s Hospital, Eugeniav\u00e4gen 23, 171 64 Solna, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"E37","DOI":"10.1016\/S2214-109X(18)30451-0","article-title":"Global, regional and national estimates of levels of preterm birth in 2014A systematic review and modeling analysis","volume":"7","author":"Chawanpaiboon","year":"2019","journal-title":"Lancet Glob. 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