Use of calcium carbonate supplementation to prevent Pre-eclampsia in pregnant women high risk: randomized clinical trial

INTERVENTION: A triple‐blind Randomized Controlled Clinical Trial (RCT) will be carried out. Pregnant women will be centrally allocated to one of three groups: experimental group I, experimental group II and control group III. As patients in the experimental group, I received daily doses of 1000 mg of calcium carbonate divided into two doses of 500 mg and 100 mg of acetylsalicylic acid in hard gelatin capsules. Patients in experimental group II receive 1000 mg of calcium carbonate from the oyster Crassostrea sp divided into two doses of 500 mg and 100 mg of acetylsalicylic acid in hard gelatin capsules and patients in the control group receive 100 mg of acetylsalicylic acid and placebo two doses per day. It was estimated that a sample of at least 120 patients in each group, with a total of 360 of the sample size in Brazil. Patients included in the study will be centrally allocated, via sealed and opaque envelopes, into one of the groups (intervention or control) according to a random coding sequence generated by the PEPI ‐ Statistical & Stat Calc Suite software. Intention‐to‐treat analysis will be adopted. The size and appearance of capsules containing only acetylsalicylic acid will be compatible with those of calcium supplements. CONDITION: C12.050.703.634 Unspecified pre‐eclampsia PRIMARY OUTCOME: A sample of at least 120 patients in each group is expected to provide 80% power to detect a 50% reduction in the incidence of PE and the estimate that 30% of high‐risk pregnant women develop pre‐eclampsia, using a two‐sided t‐test with an a level of 0.05. SECONDARY OUTCOME: No secondary outcomes are expected INCLUSION CRITERIA: Pregnant women who are up to the 20th week of pregnancy at the first stage of the approach; minumium age of 15 years; who present one or more of the risk factors: history of pre‐eclampsia, multiple pregnancy, chronic hypertension, type 1 or 2 diabetes, autoimmune disorder) will be included in the study. , kidney disease, nulliparity, body mass inde X>30 kg/m2, family history of preeclampsia (first‐degree relative), sociodemographic characteristics (African American, low socioeconomic status), age >35 years, history factors (pre‐low birth weight or small birth for gestational age, previous adverse pregnancy outcome, interval >10 years since previous pregnancy, term birth without previous complications) for the occurrence of pre‐eclampsia; and/or low intake of calcium