The association between placenta previa and the risk of breech presentation: A meta-analysis

Numerous observational studies have described that placenta previa can increase the risk of breech presentation. To date, no meta-analysis has been conducted to determine the association between placenta previa and increased risk of breech presentation. Therefore, we have done a meta-analysis based on epidemiologic evidence of the association between placenta previa and the risk of breech presentation. A literature search was done in key databases PubMed, Web of Science, Science Direct and Scopus to April 2020. The heterogeneity was evaluated by Q-test and I2 statistic. The publication bias was measured using the Begg's and Egger's tests. The results were presented by odds ratio (OR) estimate with its 95% confidence intervals (CI) using a random-effects model. The literature review involved 466 articles until April 2020 with 1,972,511 participants. There was a significant relation between placenta previa and the risk of breech presentation based on adjusted studies (OR = 1.93; 95% CI: 1.09, 2.76). To our knowledge, this was the first study that indicated placenta previa is a risk factor for breech presentation. Other studies are needed to identify which mothers with a history of placenta previa are at increased risk of breech presentation.