A bibliometric study about the subject content of the articles published in the Mexican scientific journal Archives of Medical Research is reported. The journal, published by the Mexican Institute of Social Security (IMSS), is comprised of 100 regular issues and 12 special supplements giving a total amount of 1,424 reports on medical research performed in Mexico during the last 25 years. According to the type of studies published during this period, we found that there is a similar percent of biomedical and clinical reports in the journal (47 and 42%, respectively) and a low proportion of epidemiological and medical educational reports (8 and 3%, respectively). Six thematic areas of research have been permanently published in this journal: investigations on infectious and neurological diseases being the areas mainly represented (34% of the total, corresponding to 17% in each area), followed by studies in reproductive biology (10%) and endocrine (7%), oncological (5%) and cardiovascular (3%) diseases. The tendency of the subjects covered by the journal during this period shows an increment in reports on infectious and parasitic disorders together with an increase in publications related to medicinal plant pharmacology; reproductive biology and endocrine studies show also an increasing tendency. On the other hand, a moderate decrease in studies related to neurological, oncological and cardiovascular diseases is observed. The origin of contributions during the last five years has balanced the proportion of papers published from IMSS scientists, other Mexican biomedical researchers and foreign contributions, thus reflecting favorably the recent changes in the journal's policies. This journal represents a clear example of a scientific publication edited in a developing country, originating as a national publication that evolved progressively into an international biomedical journal.