Supplementary calcium in prevention of pre-eclampsia. Nutritional factors and rest reduce pregnancy-induced hypertension and pre-eclampsia in positive roll-over test primigravidas.
To study the effect of calcium supplementation on reduction of pre-eclampsia in Iranian women at high risk of pre-eclampsia.
                Thirty pregnant women at high risk of developing pre-eclampsia were randomized to 2 g of daily calcium and placebo. Subjects and investigators were blinded to treatment allocation. The inclusion criteria were positive rollover test, having at least one risk factor for pre-eclampsia, between 28 and 32 weeks of pregnancy, and blood pressure less than 140/90 (mm Hg). Exclusion criteria were having any chronic condition. Pre-eclampsia was defined as systolic/diastolic blood pressure over 140/90 plus proteinuria. All the subjects were followed up to delivery.
                A sevenfold reduction in the occurrence of pre-eclamsia were seen among the calcium group compared with the placebo group (7 out of 15 developed pre-eclampsia in control group vs. 1 out of 15 in calcium group, P=0.014). No major effect on pregnancy induced hypertension was seen (66% in placebo and 76% in calcium group developed hypertension) but the onset of hypertension was delayed 3 weeks in the calcium group. A longer duration of pregnancy was seen in calcium than placebo (mean+/-S.D.=37+/-2 for calcium and 34+/-2 for placebo, P<0.05). Infants born to the calcium group, on average, were 552 g heavier than infants born to the placebo group, P<0.05.
                Calcium supplementation is beneficial for preventing pre-eclampsia among Iranian women at high risk of developing pre-eclampsia. The possibility of reducing pregnancy-induced hypertension and preeclampsia in primigravidas with low doses of nutritional factors and relative rest in the left lateral position was investigated in a randomized controlled, double-blind trial.
                Seventy-four normotensive women at 28-29 weeks' gestation, judged to be at risk of PIH or pre-eclampsia because they presented with a mean blood pressure of 80 mmHg or higher and a positive roll-over test, were studied. The treatment protocol was received by 37 women and the other 37 women received standard antenatal control until delivery.
                Twenty-nine (78.3%) women in the control group developed PIH and/or pre-eclampsia, as opposed to only 4 (10.8%) cases in the treatment group (P < 0.001). There were no adverse effects of treatment in mothers or in infants.
                This protocol reduces PIH and pre-eclampsia in primigravidas judged to be at risk of hypertension. Further studies are required to evaluate prostacyclin and prostaglandin E2 changes.
There is insufficient evidence for reliable conclusions about the effects of exercise on prevention of pre-eclampsia and its complications.
[Note: The four citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]