ObjectiveTo test the hypothesis that researchers in obstetrics and gynecology favor an observational type of study design.Data SourcesThe 12 regular issues ofObstetrics & Gynecologypublished during 1996 were analyzed.Method of Study SelectionAll articles in the journalObstetrics & Gynecologywere reviewed for the year 1996, except that separate issues covering case reports, case condensations, and reviews were excluded.Tabulation, Integratin, and ResultsStudies were classified as observational or experimenta. Observational studies were subclassified as either descriptive, case-control, or cohort. Experimental studies were subclassified as either randomized controlled trial (RCT) or uncontrolled trial. Other study designs were noted. Of the 316 studies published during 1996, 241 (76%) were observational, 43 (14%) experimental, and 32 (10%) other. There were 162 (51%) descriptive studies, 44 (14%) case-control studies, 35 (11%) cohort studies, 35 (11%0 RCTs, and eight (3%) uncontrolled trials.ConclusionResearchers who publish inObstetrics & Gynecologyfavor an observational study design. With evidence-based medicine growing in Popularity as a new standard or paradigm, the reliance on observational studies may have implications.