Characteristic changes in calcium metabolism in preeclamptic women in Japan

Abstract

Aim: Calcium intake is relatively low in Japanese women. The present study was to investigate longitudinal calcium metabolism during pregnancy and its characteristic changes in women with pregnancy induced hypertension (PIH) in Japan.
Methods: A total of 435 pregnant Japanese women participated in this study. Fifty nine developed PIH, including 24 with preeclampsia and 35 with gestational hypertension. The urinary calcium to creatinine (Ca/Cr) ratio and serum calcium concentrations were measured at the 1st, 2nd, and 3rd trimesters and postpartum. In preeclampsia, they were classified on focusing onset time, severity and intrauterine fetal growth.
Results: The urinary Ca/Cr ratio at the 3rd trimester was reduced, while serum calcium concentrations were reduced at the 2nd trimester in three groups. In preeclamptic women, urinary Ca/Cr ratios at 3rd trimester and after onset of disease were significantly reduced, while the serum calcium concentration at the 2nd trimester was markedly reduced. Changes in urinary calcium and serum calcium were similar in all groups of preeclampsia.
Conclusions: The characteristic changes in calcium metabolism seen in preeclampsia might be present in Japanese women, who were known to have low calcium intake.