"mild OHSS: characterised by bilateral multicystic ovarian enlargement"
"grade 1: abdominal distention and discomfort"
"grade 2: grade 1 with nausea, vomiting and/or diarrhoea, and ovarian enlargement from 5-12 cm"
"moderate OHSS: characterised by ascites and abdominal distension"
"grade 3: features of mild OHSS with ultrasonographic evidence of ascites"
"severe OHSS: characterised by hypovolaemia, haemoconcentration, thrombosis, oliguria, pleural and pericardial effusion"
"grade 4: moderate OHSS with clinical evidence of ascites and/or hydrothorax and dyspnoea"
"grade 5: grade 4 with change in blood volume, haemoconcentration, coagulation abnormalities, and diminished renal perfusion and function"
"grade 2: grade 1 with nausea, vomiting and/or diarrhoea, and ovarian enlargement from 5-12 cm"
"severe OHSS: characterised by hypovolaemia, haemoconcentration, thrombosis, oliguria, pleural and pericardial effusion"