Objectives To identify and describe controlled clinical trials (CCTs) published in Spanish Gynaecology and Obstetrics journals. In addition, to assess the quality of the CCTs on Assisted Reproduction Techniques (ART) identified in this project. Study design In order to identify eligible CCTs, all Spanish Gynaecology and Obstetrics journals were handsearched. Handsearching was conducted following the guidelines provided by the Cochrane Collaboration, which state that each journal article must be carefully reviewed, including original articles and other types of studies, letters to the editor, abstracts, and conference presentations. The results of the handsearching process were compared with an electronic search conducted in MEDLINE (PubMed). A descriptive analysis of the main characteristics of the identified CCTs was performed, as well as a methodological assessment of CCTs on ART. Results Sixteen Gynaecology and Obstetrics journals were identified, four of which have been indexed in MEDLINE at some point, although not currently. The journal with the most CCTs was "Progresos de Obstetricia y Ginecología". A total of 235 CCTs were published in these journals, of which 29 were on ART. Most CCTs (216, 91.9%) were carried out in a hospital setting; 201 (89.4%) were unicentric. Obstetrics was the most studied subspecialty (46.4%). Among CCTs on ART, the risk of bias was predominantly high. Conclusions The number of CCTs published in Spanish Gynaecology and Obstetrics journals is limited. CCTs on ART present deficiencies in the report of results and low methodological quality. It is advised that authors and journals adhere to the CONSORT statement and to the Cochrane Collaboration recommendations to reduce risk of bias when designing and disseminating research projects.