Eligible patients are those with significant ascites, diagnosed or suspected for AOC, who are scheduled for primary surgery (both upfront cytoreduction or laparoscopic evaluation before neoadjuvant chemotherapy), that cannot be performed within next 7 or more days, for any reason. Patients will be asked to fill in quality of life questionnaire (QLQ). Clinical data, a Subjective Global Assessment (SGA) will be recorded. Patients will be randomized to either intervention arm A - insertion of vascular catheter into abdominal cavity and slow, systematic, daily ascites evacuation, or to observation arm B - standard of care with just observation (acute large volume (>5000ml) paracentesis allowed if needed). Patients in both groups will be encouraged to use oral nutritional support. Randomization will be open, 1:1, for every eligible, consecutive patient. After 7 days patients will be interviewed, asked to fill in QLQ, patient's experience on the treatment survey, a SGA will be recorded. During the first hour of the surgery hemodynamic data from anethetic charts will be recorded along with other clinical data concerning patient's characteristics, surgery details and 30-day postoperative follow-up. A template is provided.