Prophylactic intravenous hydroxyethyle starch solution prevents moderate-severe ovarian hyperstimulation in in-vitro fertilization patients: a prospective, randomized, double-blind and placebo- controlled study

A prospective, randomized, double-blind and placebo-controlled study was conducted to assess the effectiveness of i.v. administration of 6% hydroxyethyle starch solution (HES) in preventing moderate and severe ovarian hyperstimulation syndrome (OHSS) in patients in an in-vitro fertilization programme. A total of 101 women who had serum oestradiol concentrations >1500 pg/ml and/or more than 10 follicles on day of human chorionic gonadotrophin (HCG) administration were recruited into two groups: HES group (n = 51) received 1000 ml 6% HES; and the placebo group (n = 50) received 1000 ml of sodium chloride 0.9% solution at the time shortly after embryo transfer. Follow-up examinations 7 +/- 1 and 14 +/- 1 days after embryo transfer included transvaginal ultrasound (diameters of each ovary and maximum cysts, number of cysts, ascites), blood tests (serum oestradiol, progesterone, beta-HCG, C-reactive protein, blood count, plasma proteins, electrolytes, kidney function tests) and evaluation of abdominal pain, nausea, diarrhoea, abdominal swelling and weight gain. Only one moderate OHSS developed in the HES group whereas seven moderate-severe cases were observed in the placebo group (P = 0.031). Furthermore, serum oestradiol concentration, leukocyte count, increase in abdominal circumference and weight gain 14 days after embryo transfer were significantly higher in the placebo group. There were no differences between the two groups in terms of age, oestradiol concentration and number of follicles at time of HCG injection. Administration of 6% HES prevents the development of moderate-severe OHSS in risk patients.