Study of a Phenylalanine Restricted Diet During Pregnancy to Prevent Symptoms in Offspring of Patients With Phenylketonuria

This study has been completed.
University of Texas
Information provided by:
Office of Rare Diseases (ORD) Identifier:
First received: August 3, 2000
Last updated: June 23, 2005
Last verified: August 2000


I. Assess the impact of a phenylalanine restricted diet during pregnancy on symptoms in offspring of patients with phenylketonuria.

Condition Intervention
Behavioral: phenylalanine restricted diet

Study Type: Interventional
Study Design: Primary Purpose: Prevention

Resource links provided by NLM:

Further study details as provided by Office of Rare Diseases (ORD):

Study Start Date: December 1983
Detailed Description:

PROTOCOL OUTLINE: This is a multicenter study.

Patients receive a phenylalanine restricted diet based on a medical food such as Phenyl-free, Lofenalac, PKU 3, or Maximum XP (may be supplemented with tyrosine as needed) to achieve a target blood phenylalanine level of 2-6 mg/dL. The diet begins approximately 3 months prior to conception and continues until delivery of the baby. Patients are evaluated once a month before conception and weekly during pregnancy. Patients also undergo sonographic examination at 8, 20, 28, and 34 weeks gestation. At birth, the cord blood is evaluated for plasma amino acids. If the baby is found to have an elevated phenylalanine level, blood and urine are obtained to determine the baby's genetic status. Phenylalanine and tyrosine levels are checked in the baby daily for three days after birth.

The baby is followed for physical and mental development at 3 and 6 months and then annually thereafter.


Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   No
  • Women with diagnosis of phenylketonuria who are planning on becoming pregnant Slightly elevated phenylalanine level (hyperphe variant) allowed
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Please refer to this study by its identifier: NCT00006142

Sponsors and Collaborators
National Center for Research Resources (NCRR)
University of Texas
Study Chair: Bobbye M. Rouse University of Texas
  More Information Identifier: NCT00006142     History of Changes
Other Study ID Numbers: 199/15326  UTMB-83-188 
Study First Received: August 3, 2000
Last Updated: June 23, 2005
Health Authority: United States: Federal Government

Keywords provided by Office of Rare Diseases (ORD):
inborn errors of metabolism
rare disease

Additional relevant MeSH terms:
Amino Acid Metabolism, Inborn Errors
Brain Diseases
Brain Diseases, Metabolic
Brain Diseases, Metabolic, Inborn
Central Nervous System Diseases
Genetic Diseases, Inborn
Metabolic Diseases
Metabolism, Inborn Errors
Nervous System Diseases processed this record on May 24, 2016