Objective: Reproductive biology is a highly productive area. By analyzing papers published in the major journals in the period 2003-2005, the collaborative patterns were characterized.
Design: Original research papers published in 2004 in the journals included in the first quartile of the category "Reproductive Biology" of the Journal Citation Reports (2005) were selected. A bibliometric analysis was carried out with the information obtained, thus building up the networks of coauthorship and institutional collaboration.
Result(s): A total of 4,702 papers were analyzed, 96.75% signed in collaboration by two or more authors, the authors per paper index being 5.24; 73.73% of the papers were collaborations between institutions. The U.S.A. and the U.K. headed the absolute productivity ranking in number of papers, and adapting the data with respect to the population, Israel, Australia, and other European countries, such as Finland, Belgium, Sweden, and The Netherlands, had notable contributions.
Conclusion(s): We identified the networks of authors who publish in the journals with the greatest impact factor. Only some of the most productive institutions have consolidated collaborative relationships with other institutions. We identified the scientific "isolation" of some countries which, although their productivity is high, have a small number of international collaborations.