Now Available for Public Comment: Notice of Proposed Rulemaking (NPRM) for FDAAA 801 and NIH Draft Reporting Policy for NIH-Funded Trials

Calcium for Pre-Eclampsia Prevention (CPEP)

This study has been completed.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI) Identifier:
First received: October 27, 1999
Last updated: June 23, 2005
Last verified: February 2002

October 27, 1999
June 23, 2005
March 1991
Not Provided
Not Provided
Not Provided
Complete list of historical versions of study NCT00000534 on Archive Site
Not Provided
Not Provided
Not Provided
Not Provided
Calcium for Pre-Eclampsia Prevention (CPEP)
Not Provided

To evaluate the efficacy of 2 grams per day of oral calcium supplementation in reducing the combined incidence of hypertensive disorders of pregnancy: pre-eclampsia, eclampsia, and the HELLP Syndrome (hypertension, thrombocytopenia, hemolysis, and abnormal liver function). The National Institute of Child Health and Human Development (NICHD) initiated the trial in 1991, with joint funding provided by the National Heart, Lung, and Blood Institute in fiscal years 1992, 1993, and 1995.


A considerable body of data has associated lower blood pressures with higher levels of dietary calcium. Epidemiologic studies, laboratory evaluations, and clinical trials have also indicated that the incidence of hypertensive disorders of pregnancy is affected similarly by calcium intake. A meta-analysis of five controlled clinical trials of calcium supplementation in pregnancy suggested a significant reduction in proteinuric pre-eclampsia of 46 percent. Several of the trials, however, suffered from 'pitfalls' in the diagnosis of pre-eclampsia, including lack of blinding, uncertain definition of endpoints, and unknown techniques of measurement. Most trials have not assessed the role of dietary nutrients or the possibility that a subgroup with low baseline urinary calcium may benefit most from calcium supplementation. In no trial has the potential for increased risk of kidney stones in the treatment group been examined systematically. Moreover, the daily schedule for administration of calcium, has generally not been reported. There was a great need, therefore, to evaluate the efficacy of calcium supplementation for the prevention of pre-eclampsia in a large multicenter controlled clinical trial. The trial considered the role of dietary nutrients, establish whether treatment is beneficial only for those with low baseline urinary calcium, conduct systematic surveillance for urolithiasis, and employ standardized terminology, techniques of measurement, and diagnostic criteria. The NHLBI provided funding to NICHD for three years by means of an Intraagency Agreement (Y01HC20154).


Randomized, double-blind, multicenter. Healthy nulliparous patients were randomly assigned to receive either 2 grams of supplemental calcium daily ((n = 2,295) or placebo (n = 2,294) in a double-blind study. Study tablets were administered beginning from 13 to 21 completed weeks of gestation and continued until the termination of pregnancy. Eligible patients entered a run-in period of 6 to 14 days to exclude highly noncompliant subjects. During the run-in, obstetrical ultrasound was performed if it had not been obtained previously, and blood was drawn for serum calcium and creatinine. Follow-up visits were scheduled every four weeks through the 29th week of gestation, then every two weeks through the 35th week, and weekly thereafter. Blood pressure and urine-protein were obtained at each clinic visit, during labor and delivery, and during the first 24 hours postpartum. Primary endpoints included pregnancy-associated hypertension, pregnancy-associated proteinuria, pre-eclampsia, eclampsia, or hypertension. Other endpoints included placental abruption, cerebral hemorrhage or thrombosis, elevated liver enzymes, acute renal failure, and disseminated intravascular coagulation. Surveillance was conducted for renal calculi. Recruitment began in May 1992 and ended in March 1995. Follow-up was completed in October of 1995. Data analysis continued through March 2000 under the NICHD contract N01HD13121.

Phase 3
Masking: Double-Blind
Primary Purpose: Prevention
  • Cardiovascular Diseases
  • Eclampsia
  • Heart Diseases
  • HELLP Syndrome
  • Hypertension
  • Pre-Eclampsia
  • Pregnancy Toxemias
  • Vascular Diseases
  • Drug: calcium
  • Behavioral: dietary supplements
Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Not Provided
June 2000
Not Provided

Nulliparous, normotensive, pregnant women.

18 Years to 40 Years
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Not Provided
National Heart, Lung, and Blood Institute (NHLBI)
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Investigator: Patrick Catalano Case Western Reserve University
Investigator: Luis Curet University of New Mexico
Investigator: John Hauth University of Alabama at Birmingham
Investigator: Cynthia Morris Oregon Health and Science University
Investigator: Baha Sibai University of Tennessee
National Heart, Lung, and Blood Institute (NHLBI)
February 2002

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP