Does serum calcium in pre-eclampsia and normal pregnancy differ?

OBJECTIVE: To determine the calcium and parathyroid hormone levels in normal pregnancy and pregnancy induced hypertension.

METHODS: Eighty pregnant women were enrolled in this study, 50 women represented the study group (Pregnancy-induced hypertension), and 30 women represented the control group (normal pregnancy). This study was carried out between March 1998 to February 2000 at King Hussein Medical Center, starting from the first or 2nd trimester. Once the patient developed hypertension for the first time in the 3rd trimester and fullfilled the selected criteria she was enrolled in this study.

RESULTS: The mean serum total calcium of the study group was (8.22±0.12mg%), while the mean serum total calcium of the control group was (9.50±0.16mg%). There was a statistical significance between the 2 groups, lower in the study group P<0.005. Serum parathyroid hormone concentration was significantly higher in the study group P< 0.005.

CONCLUSION: It has been widely documented that there is a relationship between low calcium level and pregnancy induced hypertension. Our study suggests that maternal serum total calcium and parathyroid hormone be related to pregnancy-induced hypertension. The low level of maternal total calcium may have a role in the development of this disorder in pregnancy, therefore calcium supplementation during late pregnancy may be used to help in the prevention of this disorder. However, to date there is still no evidence regarding this supplementation and there are no available reports conclusively demonstrating the actual mechanism.