Abstract
We performed a systematic review on the clinical epidemiology and outcome of difficult embryo transfers (ETs) in infertility patients who present with difficult ET. We searched PubMed, ScienceDirect, and Elsevier journals from 1980 to June 2017. We aimed to determine the most successful method resulting in highest pregnancy rates (PRs) in patients with difficult ET. We identified 50 articles, in which 36 were reviewed and 15 were included. Analysis of the data collected showed that the majority of the difficult ETs were caused by cervical stenosis and the most common treatment was cervical dilation. We concluded that cervical dilation was effective at managing difficult ET. Hegar dilators used a minimum of 3 weeks before ET showed to have higher PR.