Oral Micronized Progesterone 200 mg/day versus 600 mg/day for Maintenance Tocolysis after Arrested Preterm Labor: A randomized controlled trial
Article Sidebar
Main Article Content
Abstract
Objectives: To compare the efficacy of oral micronized progesterone 200 mg/day versus 600 mg/day in maintaining pregnancy after arrested preterm labor.
Materials and Methods: A single-center randomized controlled trial was conducted at Queen Savang Vadhana Memorial Hospital, Thailand (June 2023–January 2024). Pregnant women with preterm labor between 24+0 and 33+6 weeks’ gestation, successfully treated with acute tocolysis, were randomized to receive either oral micronized progesterone 200 mg/day or 600 mg/day until 36 weeks. The primary outcome was the rate of term delivery. Secondary outcomes included gestational age at delivery, latency period, birth weight, neonatal outcomes, and adverse drug effects.
Results: Ninety-eight women were randomized (49 per group). Baseline characteristics were comparable. Term delivery occurred in 79.6% of women in the 200 mg group versus 73.5% in the 600 mg group (p = 0.475). Median latency was 34 days (interquartile range, IQR 28.5, 47) and 39 days (IQR 26, 47.5), respectively (p = 0.820). Mean gestational age at delivery was 37.3 ± 1.4 weeks vs 37.1 ± 2.1 weeks (p = 0.531). Mean birth weight was 2,874 ± 418 g vs 2,833 ± 503 g (p=0.663). Two neonates (4.1%) in the 600 mg group developed hypoxia and one (2%) required neonatal intensive care unit admission; none occurred in the 200 mg group. No severe maternal side effects were observed.
Conclusion: The efficacy of oral micronized progesterone 200 mg/day was not different from 600 mg/day in maintaining pregnancy after arrested preterm labor. Due to the absence of a placebo group, the study cannot conclude that oral micronized progesterone is effective for maintenance tocolysis after arrested preterm Labor.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
References
Cunningham FG, Leveno KJ, Dashe JS, Hoffman BL, Spong CY, Casey BM. Preterm birth. Williams obstetrics. 26th ed. New York: McGraw-Hill 2022; 783-814.
Royal Thai College of Obstetricians and Gynaecologists. Preterm birth prevention guidelines [Internet]. Bangkok: RTCOG 2024.
Sukhopon W, Anakrat W, Pradyachaipimon A. The prevalence of preterm delivery and adverse pregnancy outcomes in healthy singleton teenage pregnancies at Charoenkrung Pracharak Hospital. Thai J Obstet Gynaecol 2021;29:298-304.
Kinpoon K, Chaiyarach S. The incidence and risk factors for preterm delivery in Northeast Thailand. Thai J Obstet Gynaecol 2021;29:100-111.
World Health Organization. Preterm birth [Internet]. Geneva: World Health Organization 2023.
Gaunekar NN, Raman P, Bain E, Crowther CA. Maintenance therapy with calcium channel blockers for preventing preterm birth after threatened preterm labour. Cochrane Database Syst Rev 2013; 10:CD004071.
Dodd JM, Crowther CA, Middleton P. Oral betamimetics for maintenance therapy after threatened preterm labour. Cochrane Database Syst Rev 2012;12: CD003927.
Eke AC, Chalaan T, Shukr G, Eleje GU, Okafor CI. A systematic review and meta-analysis of progestogen use for maintenance tocolysis after preterm labor in women with intact membranes. Int J Gynaecol Obstet 2016;132:11–6.
Breuking SH, De Ruigh AA, Hermans FJR, Schuit E, Combs CA, Tejada BM, et al. Progestogen maintenance therapy for prolongation of pregnancy after an episode of preterm labour: A systematic review and meta-analysis. Br J Obstet Gynaecol 2023;130:1306–16.
Choudhary M, Suneja A, Vaid NB, Guleria K, Faridi MMA. Maintenance tocolysis with oral micronized progesterone for prevention of preterm birth after arrested preterm labor. Int J Gynecol Obstet 2014;126:60-3.
Sharami SH, Zahiri Z, Shakiba M, Milani F. Maintenance therapy by vaginal progesterone after threatened idiopathic preterm labor: a randomized placebo-controlled double-blind trial. Int J Fertil Steril 2010;4:45-50.
Hyett J, Asadi N, Khafri MZ, Vafaei H, Kasraeian M, Salehi A, et al. Vaginal progesterone as maintenance therapy in women with arrested preterm labor: a double-blind placebo RCT. J Matern Fetal Neonatal Med 2022;35:1134-40.
Arikan I, Barut A, Harma M, Harma IM. Effect of progesterone as a tocolytic and in maintenance therapy during preterm labor. Gynecol Obstet Invest 2011;72:269-73.
Nachum Z, Ganor Paz Y, Massalha M, Wated M, Harel N, Yefet E. Vaginal progesterone for pregnancy prolongation after arrested preterm labor: a randomized clinical trial. JAMA Netw Open 2024;7:e2419894.
Areeruk W, Phupong V. A randomized, double-blinded, placebo-controlled trial of oral dydrogesterone supplementation in the management of preterm labor. Sci Rep 2016;6:20638.
Thongchan S, Phupong V. Oral dydrogesterone as an adjunctive therapy in the management of preterm labor: a randomized, double-blinded, placebo-controlled trial. BMC Pregnancy Childbirth 2021;21:90.
Sirisangwon R, Phupong V. Vaginal progesterone supplementation in the management of preterm labor: a randomized controlled trial. Matern Child Health J 2021;25:1102-9.
Besins Healthcare. Utrogestan® 200 MG [Internet]. Singapore: Food and Drug Administration 2023
Shynlova O, Nadeem L, Lye S. Progesterone control of myometrial contractility. J Steroid Biochem Mol Biol 2023;234:106397.
