INTRODUCTION Beside medical, nonmedical factors also influence the quantity and structure of administered drugs. Therefore, it is of importance to analyze these factors and their influence on drug consumption in perinatological hospital practice. The aim of this study was to analyze pharmacotherapeutic practice as well as the influence of nonmedical factors on drug use at the Institute of Perinatology of the Department of Obstetrics and Gynaecology in Novi Sad. MATERIAL AND METHODS The study was of retrospective-prospective character. Analyses comprised drug consumption for the period 1989 and the first 6 months of 1993 and 1994 analyzing data obtained from the hospital pharmacy. Due to lack of drug supply in the hospital pharmacy and domestic market, a sample of 10% patient's histories were taken for analysis in order to compare the above data for the same time interval. All drugs were classified according to the unique ATC (Anatomical Therapeutic Chemical) classification, where the Defined Daily Dose (DDD) was taken as the drug use statistical unit. RESULTS AND DISCUSSION According to the data from the hospital pharmacy, the total drug consumption in 1989 was 7301,85 DDD/BD and in 1993 and 1994 it was significantly decreased (1993--5135,80 DDD/1000 BD vs. 1994--2095,90 DDD/1000 BD). Majority of drugs for all the investigated periods were administered for the group G (urogenital system and sex hormones) out of which most often used drugs were G02A (drugs for stimulation of uterine contractions). According to the patients' history data, drug use was significantly increased in 1993--6322,22 DDD/1000 BD and 1994--3340,01 DDD/1000 BD. The only exception was group A (alimentary tract and metabolism) in which, according to history data, drugs were significantly less frequently prescribed than supplied. The greatest difference in the quantity of prescribed drugs (patients' history data) and the drugs issued from the hospital pharmacy was recorded in the group C (cardiovascular system), G (urogenital system and sex hormones) and H (hormones for systemic use with sex hormones excluded). Prescription of drugs from the groups C and H respectively, according to history data was most probably justified, but a question is raised concerning high rate of drug prescription in group G.