en Original Article Original Article <div style="text-align: justify;">The authors have been informed that some errors occurred on their published article entitled &quot;Effect of vitamin D insufficiency treatment on fertility outcomes in frozen-thawed embryo transfer cycles: A randomized clinical trial&quot; [Iran J Reprod Med 2014; 12: 595-600] in the time of study and the tables which do not affect the article&#39;s conclusion. The completion date of the investigation was changed from April 2014 to February 2014. Also, the study results were re-analyzed, and some minor modifications were made in the numbers mentioned in the tables without affecting the overall meaning and concept of the study.<br> The author&#39;s wishe to apologize for these errors. The online version of the article has been updated on 12 June 2017 and can be found at http://dx.doi.org/10.18502/ijrm.v17i12.5801</div> vitamin D,treatment,frozen-thawed 68 68 http://ijrm.ir/browse.php?a_code=A-10-229-6&slc_lang=en&sid=1 Abbas Aflatoonian 0000-0002-2896-6136 No Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Farideh Arabjahvani f_arabjahvani@yahoo.com Yes Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Maryam Eftekhar 0000-0003-3835-5635 No Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Mozhgan Sayadi No Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.