I O Evbuomwan1, J M Davison, A P Murdoch. 1. International Centre for Life and Royal Victoria Infirmary, Newcastle upon Tyne Hospitals NHS Trust, United Kingdom. ievbuomwan@talk21.com
Abstract
OBJECTIVE: To investigate the concomitant time courses of the changes in osmolality and calculated blood volume during the genesis of ovarian hyperstimulation syndrome (OHSS). DESIGN: Prospective longitudinal study. SETTING: IVF-ET program in a university-based assisted reproductive technology center. PATIENT(S): Thirty women undergoing superovulation for IVF-ET. INTERVENTION(S): Blood and urine samples were obtained on seven occasions from the start of FSH stimulation until a pregnancy test. Five women with severe OHSS had daily blood and urine tests during hospitalization. MAIN OUTCOME MEASURE(S): Changes in serum and urine osmolality, serum electrolytes, albumin, hemoglobin, and hematocrit. RESULT(S): Blood volume in women with OHSS decreased significantly by 20% from days hCG +2 to +4, followed by a sustained increase of 30% above baseline from days hCG +8 to +12. There was no statistically significant change in blood volume in women without OHSS. There was a sharp decrease in serum osmolality in women without OHSS between days 0 and hCG +2, which recovered toward baseline from day 4 after hCG. In women with OHSS, there was an unexpected increase in osmolality of 6 mOsm/kg between days hCG -2 and 0, followed by a decrease of 8 mOsm/kg by day hCG +2; this was sustained until day hCG +12. Patients with OHSS demonstrated a concentration and dilution of their urine during the acute and recovery phases of the syndrome, respectively, despite persistence of the hypoosmolar state. CONCLUSION(S): Decreased osmolality in severe OHSS is maintained despite significant decreases and increases in blood volume, suggestive of fundamental alterations in osmoregulation.
OBJECTIVE: To investigate the concomitant time courses of the changes in osmolality and calculated blood volume during the genesis of ovarian hyperstimulation syndrome (OHSS). DESIGN: Prospective longitudinal study. SETTING:IVF-ET program in a university-based assisted reproductive technology center. PATIENT(S): Thirty women undergoing superovulation for IVF-ET. INTERVENTION(S): Blood and urine samples were obtained on seven occasions from the start of FSH stimulation until a pregnancy test. Five women with severe OHSS had daily blood and urine tests during hospitalization. MAIN OUTCOME MEASURE(S): Changes in serum and urine osmolality, serum electrolytes, albumin, hemoglobin, and hematocrit. RESULT(S): Blood volume in women with OHSS decreased significantly by 20% from days hCG +2 to +4, followed by a sustained increase of 30% above baseline from days hCG +8 to +12. There was no statistically significant change in blood volume in women without OHSS. There was a sharp decrease in serum osmolality in women without OHSS between days 0 and hCG +2, which recovered toward baseline from day 4 after hCG. In women with OHSS, there was an unexpected increase in osmolality of 6 mOsm/kg between days hCG -2 and 0, followed by a decrease of 8 mOsm/kg by day hCG +2; this was sustained until day hCG +12. Patients with OHSS demonstrated a concentration and dilution of their urine during the acute and recovery phases of the syndrome, respectively, despite persistence of the hypoosmolar state. CONCLUSION(S): Decreased osmolality in severe OHSS is maintained despite significant decreases and increases in blood volume, suggestive of fundamental alterations in osmoregulation.