[Predictive value of urinary calcium measurement on occurrence of pregnancy-induced hypertension].

OBJECTIVE

To study the predictive value of urinary calcium excretion on occurrence of pregnancy-induced hypertension (PIH).

METHODS

Twenty-four-hour urinary calcium excretion, urinary calcium concentration and urinary calcium/creatinine (Ca/Cr) ratio were determined in 184 normal pregnant women and 30 patients with PIH.

RESULTS

Twenty-four-hour urinary calcium excretion, urinary calcium concentration, and Ca/Cr ratio in PIH group were significantly lower than that in normal pregnant group (P < 0.01). 3 mmol/L of urinary calcium concentration and 0.04 of Ca/Cr ratio were chosen as predictive thresholds for development of PIH, with sensitivity of 76.2%, 81.0% and specificity of 97.5%, 98.2% respectively.

CONCLUSIONS

Low urinary calcium excretion is a valuable marker for prediction of PIH.