<P> Control of metabolism is vital during pregnancy of women with MSUD . To prevent detrimental abnormalities in development of the embryo or fetus, dietary adjustments should be made and plasma amino acid concentrations of the mother should be observed carefully and frequently . Amino acid deficiency can be detected through fetal growth, making it essential to monitor development closely . </P> <P> Maple syrup urine disease (MSUD) is a rare, inherited metabolic disorder . Its prevalence in the United States population is approximately 1 newborn out of 180,000 live births . However, in populations where there is a higher frequency of consanguinity, such as the Mennonites in Pennsylvania or the Amish, the frequency of MSUD is significantly higher at 1 newborn out of 176 live births . In Austria, 1 newborn out of 250,000 live births inherits MSUD . It also is believed to have a higher prevalence in certain populations due in part to the founder effect since MSUD has a much higher prevalence in children of Amish, Mennonite, and Jewish descent . </P>

What is the cause of maple syrup urine disease