Absorption of irrigating solution during transcervical resection of endometrium can cause dilutional hyponatraemia, nausea, and cerebral oedema. We studied 6 patients who absorbed more than 1500 mL of 1.5% glycine, and 14 patients who absorbed less. Cerebral oedema was diagnosed by blinded, paired comparison of computed tomography (CT) scans 3-6 hours and 3-6 days after operation. The absorbed volume of irrigating glycine solution was correlated with peroperative decrease in serum sodium. 10 patients who absorbed 500 mL of glycine or more had postoperative nausea, with cerebral oedema suspected in 9. None of the 10 patients who absorbed less than 500 mL had nausea; changes on CT scan suggestive of cerebral odema were found in 1. 8 patients who absorbed 1000 mL or more had a decrease in serum sodium of 10 mmol/L or more, nausea, and cerebral oedema on CT scan. Cerebral oedema may contribute to the development of postoperative nausea in patients undergoing transcervical surgery who absorb more than 500 mL of 1.5% glycine irrigating solution.