Manoochehr Karami1, Ensiyeh Jenabi2, Bita Fereidooni3. 1. a Social Determinates of Health Research Center , Hamadan University of Medical Sciences , Hamadan , Iran. 2. b Department of Midwifery, Toyserkan Branch , Islamic Azad University , Toyserkan , Iran. 3. c Midwife in Social Security Organization , Hamadan , Iran.
Abstract
BACKGROUND: Several epidemiological studies have determined that assisted reproductive techniques (ART) can increase the risk of placenta previa. To date, only a meta-analysis has been performed for assessing the relationship between placenta previa and ART. This meta-analysis was conducted to estimate the association between placenta previa and ART in singleton and twin pregnancies. METHODS: A literature search was performed in major databases PubMed, Web of Science, and Scopus from the earliest possible year to April 2017. The heterogeneity across studies was explored by Q-test and I2 statistic. The publication bias was assessed using Begg's and Egger's tests. The results were reported using odds ratio (OR) and relative risk (RR) estimates with its 95% confidence intervals (CI) using a random-effects model. RESULTS: The literature search yielded 1529 publications until September 2016 with 1,388,592 participants. The overall estimate of OR was 2.67 (95%CI: 2.01, 3.34) and RR was 3.62 (95%CI: 0.21, 7.03) based on singleton pregnancies. The overall estimate of OR was 1.50 (95%CI: 1.26, 1.74) based on twin pregnancies. CONCLUSIONS: We showed based on odds ratio reports in observational studies that ART procedures are a risk factor for placenta previa.
BACKGROUND: Several epidemiological studies have determined that assisted reproductive techniques (ART) can increase the risk of placenta previa. To date, only a meta-analysis has been performed for assessing the relationship between placenta previa and ART. This meta-analysis was conducted to estimate the association between placenta previa and ART in singleton and twin pregnancies. METHODS: A literature search was performed in major databases PubMed, Web of Science, and Scopus from the earliest possible year to April 2017. The heterogeneity across studies was explored by Q-test and I2 statistic. The publication bias was assessed using Begg's and Egger's tests. The results were reported using odds ratio (OR) and relative risk (RR) estimates with its 95% confidence intervals (CI) using a random-effects model. RESULTS: The literature search yielded 1529 publications until September 2016 with 1,388,592 participants. The overall estimate of OR was 2.67 (95%CI: 2.01, 3.34) and RR was 3.62 (95%CI: 0.21, 7.03) based on singleton pregnancies. The overall estimate of OR was 1.50 (95%CI: 1.26, 1.74) based on twin pregnancies. CONCLUSIONS: We showed based on odds ratio reports in observational studies that ART procedures are a risk factor for placenta previa.