ORIGINAL ARTICLE Bali Medical Journal (Bali Med J) 2016, Volume 5, Number 1: 38-44 P-ISSN.2089-1180, E-ISSN.2302-2914 38 Open access: www.balimedicaljournal.org and ojs.unud.ac.id/index.php/bmj CrossMark Published by DiscoverSys 1 Obstetrics & Gynecology, Mehr Hospital, Borazjan, Iran 2 Associate Professor, Healthcare Management Department, Shahid Sadoughi University of Medical Sciences, Yazd, Iran 3 Obstetrics & Gynecology, Ayatollah Khatami Hospital, Yazd, Iran 4 Medicine Student, Shahid Sadoughi University of Medical Sciences, Yazd, Iran 5 Orthopedic Resident, Shahid Beheshti University of Medical Sciences, Tehran, Iran 6 Assistant Professor, Health Sciences Research Center, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran 7 Assistant professor, Healthcare management department, Shiraz university of medical sciences, Shiraz, Iran ABSTRACT Background: Preterm labor is a common complication of pregnancy which has become a main health concern around the world due to its negative consequences. Objective: To investigate the efficacy of progesterone therapy in the prevention of preterm labor in women with single risk factor. Search strategy: A PubMed, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Science Direct, Scopus, OVID, EMBASE, SID, Magiran and Google Scholar search (date last searched April 2016) without any time, language and location restriction was done. Inclusion criteria: All randomized clinical trials of singleton pregnancies with single risk factor (prior preterm labor without short cervical length or short cervical length without prior preterm labor) which were randomized to progesterone and control groups were included in our meta-analysis. Primary outcome: Our primary outcome was gestational age at delivery. Results: 13 studies (1259 subjects and 2653 control women) were included in the meta-analysis. Using random effect model showed that mean gestational age at delivery of progesterone group is 0.74 (0.41- 1.06) month longer than that of control group with CI=95% which is significant statically. Conclusions: Progesterone therapy is an effective intervention for the prevention of preterm labor in women with single risk factor. Keywords: Preterm birth, Preterm labor, Previous preterm labor, Progesterone, Short cervical length. Cite This Article: Chaman-Ara, K., Bahrami, M., Bahrami, E., Bahrami, S., Bahrami, M., Moosazadeh, M., Barati, O. 2016. Progesterone Therapy for the Prevention of Preterm Labor in Women with Single Risk-factor: A Systematic Review and Meta-analysis. Bali Medical Journal 5(1): 38-44. DOI:10.15562/bmj.v5i1.193 INTRODUCTION Preterm labor which is defned as the delivery afer 20 weeks and before 37 completed weeks of gestation is a common complication of pregnancy worldwide. 1-4 Reports indicate that between 5 to 25 percent of all pregnancies are resulted in preterm labor. Te prevalence of preterm labor is diferent in diferent populations. In 2010, about 12% of all live births in US, 8% in Canada, 5-15% in developed countries and more than 23% in India has been occurred premature. 6-13 Preterm birth is a multi-causal condition infuenced by various factors. 14-20 Preterm birth has very negative consequences and is the most important cause of infant mortality and long-term disability. 1,2,13 Respiratory distress syndrome and chronic lung disease which are the most important complica- tions of premature birth and the leading causes of infant mortality, Cerebral palsy, neurological prob- lems and sensory-motor disability, heart defects, increased risk of heart disease (heart attack, stroke and hypertension) and diabetes in adulthood, vision loss and blindness, hearing defects, patent ductus, bronchopulmonary dysplasia, intracranial infections and bleeding, necrotizing enterocolitis, asphyxia, retinopathy of prematurity, sudden infant death syndrome and the long-term mental and develop- mental disabilities are among the most common complications which premature infants faced with them. Also, the prematurely born babies, ofen expe- rience cognitive, behavioral and social problems in adulthood and their educational achievements are poor. Tese problems increase the social costs of preterm birth for premature born babies, their families and societies and lead to an increased need to treatment assistance and psychological disorders with its following negative consequences. 3-17 Terefore, the preventing from preterm birth has become a top concern of health decision makers and practitioners around the world due to its wide- spread adverse consequences. 6-8 Te frst step in the prevention of preterm labor is the sound identifca- tion of at risk pregnant women. 13 Several indicators can help to predict preterm labor 3 but most studies have shown that the most powerful predictors of Progesterone therapy for the prevention of preterm labor in women with single risk-factor: a systematic review and meta-analysis Kefayat Chaman-Ara, 1 Mohammad Amin Bahrami, 2 Elham Bahrami, 3* Sima Bahrami, 4 Mohammad Nabi Bahrami, 5 Mahmood Moosazadeh, 6 Omid Barati 7 * Correspondence to: Elham Bahrami Obstetrics & Gynecology, Ayatollah Khatami Hospital, Yazd, Iran dr.bahramie7531@gmail.com