The effects of hemodialysis on total intrauterine volume.

Our objective was to assess the effects of maternal fluid shifts during hemodialysis on the amniotic fluid volume. Ultrasound estimation of the total intrauterine volume before and after dialysis was performed between 23 and 26 weeks in a 30-year-old woman with progressive IgA glomerulonephropathy. The total intrauterine volume was reduced after each episode of dialysis. The mean decrease in the amniotic fluid volume was 116.6 ml (range 17.8-287.1 ml), which represented a 1.5-31.1% change in the total intrauterine volume (p = 0.004). The reduction was linearly related to the amount of maternal fluid removed during hemodialysis. The reduction in the total intrauterine volume was best estimated by the equation: -6.618 + (32.582) (weight loss in kilograms). Hemodialysis during pregnancy results in linear amniotic fluid shifts related to the amount of maternal fluid removed during dialysis. Given these findings, care must be taken to limit the volume of maternal fluid removed during hemodialysis, especially in pregnancies complicated by early gestation, intrauterine growth retardation, or oligohydramnios.