[Urinary calcium excretion as an early prediction marker for pregnancy induced hypertension].

Two hundred and forty-nine healthy women at 36 weeks gestation and 38 women with pregnancy induced hypertension (PIH) underwent urinalysis for urinary calcium excretion to obtain the calcium/creatinine ratio. This ratio was significantly lower in the women with PIH than in the healthy pregnant women, and it was especially low in those with PIH who had no family history of hypertension. Three hundred forty-eight healthy women at 20 weeks of gestation underwent urinalysis to determine their calcium/creatinine ratio as a means to predict PIH in patients showing no symptoms. In the primiparous group with no family history 58% of the patients with a low calcium/creatine ratio eventually developed PIH. Using a receiver operator curve, we calculated a predictive threshold calcium value for PIH of 0.06 at six month's pregnancy. Thus urinary calcium excretion may be a useful early marker for PIH.