OBJECTIVES: Our aim was to examine the changes of body composition in the perioperative period. METHODS: The authors examine the body composition of 11 postmenopausal women (Total Body Water (TBW), Extracellular Water (EW), Intracellular Water (IW), Fat Mass (FM), Fat Free Mass (FFM)) 1month and 1 day before as well as 1day and 1 month after the operation. The performed operations were anterior colporrhaphy with or without posterior colporrhaphy or enterocele repair. Preoperative medical preparation ordered the use of oral (1mg estriol/die; T. Ovestin) and local (U. Ovestin; 1mg/g estriol) estrogen for a month. Fluid replacement was adequate as ordered for patients with first-degree severity (average operative load, prohibition of fluid intake is not longer than 6-12 hours, maximum blood loss is 250-500 ml) during the operation and in the postoperative period. Body composition parameters were measured by MF HUMAN –IM SCAN Master 1.0. The statistical data were calculated according to mean, standard deviation, median, range, Fisher’s exact test, Student’s t-test methods and the results were considered to be significant at p<0,05. RESULTS: The mean age of the subjects was 59.4 years (8.58 SD, median 57 years, range 48-72 years), the average number of preceding pregnancies was 3.33 (1.68 SD) with 2,46 deliveries (1.46 SD). In the preoperative period (between the 1st and the 2nd measurements) a significant decrease (p=0,056) was found in EW. In comparison of the 2nd and the 3rd measurements a significant decrease (ECW p=0,027; TBW p=0,04; FM p=0,019; FFM p=0,019) was observed except for the parameters of ICW (p=0,15). Between the 1st and 30th day after the surgery changes in findings were not significant (ECW p=0,81; TBW p=0,83; FM p=0,5; FFM p=0,3; ICW p=0,616). CONCLUSIONS: The results suggest that body composition changes in the perioperative period should be followed.