Obstetrics & Gynecology

Skip Navigation LinksHome > Citations and Impact Factor

Citations and Impact Factor

Citation data are an important part of evaluating a scientific journal. Below, we provide data on metrics used by Obstetrics & Gynecology as well as tools for readers available on our web site.


In June of each year, several metrics using citation data are released to publishers and scientific journals. One well-known metric is the impact factor, which is "a measure of the frequency with which the 'average article' in a journal has been cited in a particular year or period."1

Obstetrics & Gynecology's 2014 impact factor is 5.175. The journal's ranking is the second highest impact factor out of all 79 obstetrics and gynecology journals. Five-year history is available in the Table.

 Year  Impact Factor  Ranking
 2014  5.175  2nd of 79 journals
 2013  4.368  3rd of 78 journals
 2012  4.798  2nd of 77 journals
 2011  4.730  2nd of 79 journals
 2010  4.392  2nd of 75 journals

The 5-year impact factor is "the average number of times articles from the journal published in the past 5 years have been cited" in a particular year.2 Obstetrics & Gynecology’s 2014 5-year impact factor is 5.098, which is the second highest in the field.

The immediacy index is the "average number of times an article is cited in the year it is published."3 Obstetrics & Gynecology’s 2014 immediacy index is 1.209, which ranks it in the top ten titles in obstetrics and gynecology.

The Eigenfactor score is a calculation "based on the number of times articles from the journal published in the past five years have been cited in [a particular] year, but it also considers which journals have contributed these citations so that highly cited journals will influence the network more than lesser cited journals. References from one article in a journal to another article from the same journal are removed, so that Eigenfactor Scores are not influenced by journal self-citation."4 Obstetrics & Gynecology’s 2014 Eigenfactor score is 0.04815, which ranks it in the top five titles in obstetrics and gynecology.

For more information on the impact factor, see Benner RS. Evaluating the importance of a journal: the impact factor and other metrics. Obstet Gynecol 2012;119:3–4.

Web Site Tools

The Obstetrics & Gynecology web site features tools that will make tracking important research easy:

  1. Alert Me When Cited allows registered users to receive an e-mail alert every time an article is cited by another article. To take advantage of this feature, simply look in the “Article Tools” box on the right side of the screen when viewing an article at GreenJournal.org.
  2. Cited By is a list of articles that have cited a given article, and can be found at the end of the full-text HTML version of an article, following its reference list. Hyperlinks in the Cited By list enable you to link out to PubMed and locate the article on the web via CrossRef functionality.
  3. Highest Impact articles are identified at Greenjournal.org in addition to the most viewed and most e-mailed articles. A special filter is employed to detect articles with rapid citation activity (articles that have been cited more quickly than the average article). The result is a list of what are often key papers in the field.


  1. The Thomson Reuters Impact Factor. Available at: http://thomsonreuters.com/products_services/science/free/essays/impact_factor/. Retrieved July 7, 2011.
  2. Thomson Reuters. Journal Citation Reports: Impact Factor. Available at: http://admin-apps.isiknowledge.com/JCR/help/h_impfact.htm. Retrieved July 8, 2011.
  3. Thomson Reuters. Journal Citation Reports: Immediacy Index. Available at: http://admin-apps.webofknowledge.com/JCR/help/h_immedindex.htm. Retrieved June 24, 2015.
  4. Thomson Reuters. Journal Citation Reports: Eigenfactor Metrics. Available at: http://admin-apps.isiknowledge.com/JCR/help/h_eigenfact.htm. Retrieved July 8, 2011.