Maternal Inborn Errors of Metabolism in Pregnancy: A Pregnancy Registry Protocol
Condition: Inborn Errors of Metabolism; Pregnancy; Acidemias
MeSH terms: Metabolism, Inborn Errors
Study type: Observational

Summary: 
      Background:

      - People with inborn errors of metabolism can t turn food into energy the right way. This can
      affect a person s growth and health. Researchers want to know how this condition affects a
      pregnant woman and her baby.

      Objectives:

      - To collect data from the medical records of women with an inborn error of metabolism. Also,
      to create a pregnancy registry of inborn errors of metabolism.

      Eligibility:

        -  Women with an inborn error of metabolism who either:

        -  have been pregnant in the past,

        -  are currently pregnant, or

        -  have recently talked with their doctor about becoming pregnant.

      Design:

        -  This study will collect data only. No extra tests will be done.

        -  Participants will be in the study for the length of their pregnancy and for 1 year after
           delivery.

        -  Participants will answer questions about their family s health.

        -  The participant s doctor will send their medical records to researchers. These may
           include data about:

        -  Last health care visit before pregnancy

        -  Blood, urine, ultrasound, or lab results during pregnancy

        -  Delivery and recovery after delivery

        -  Researchers will ask for the test(s) used to confirm pregnancy.

        -  After the participant has her baby, researchers will ask for data about how the baby is
           doing. This may include when the baby is sitting, walking, talking, etc.

        -  The data will be placed into a database. The database will not include the participant s
           name or identifying data.
    

Detailed description: 
      Women with inherited metabolic disorders are reaching child bearing age more often due to
      advances in early diagnosis and improved pediatric care. For many of these disorders, there
      is very little information in the literature to guide the counseling and treatment of these
      patients and their pregnancies.

      The most information for the effects of an underlying inborn error of metabolism in pregnancy
      derives from the study of phenylketonuria (PKU). From the knowledge gained through the
      collection of information from multiple cases of pregnancy affected by PKU, important
      management issues were identified. For example, children born to mothers with an unrestricted
      diet were substantially more likely to have intellectual disability, microcephaly, and low
      birth weights than women who maintained a phenylalanine restricted diet. The excess
      phenylalanine poses long-term health risks to the developing fetus and now a vigilant
      metabolic approach is recognized as mandatory in women with PKU desiring pregnancy.

      Compared to PKU, most or all other intermediary metabolic disorders have been understudied.
      For example, there are nine published cases of methylmalonic acidemia (MMA) in pregnancy and
      one case of cobalamin C deficiency in pregnancy, and review articles have reported the same
      cases. For other inborn errors of metabolism there is even less published or known. The
      paucity of publication of pregnancy in IEMs other than PKU may be due to the lack of
      organized research to address pregnancy management in metabolic disorders.

      The objective of this study is to establish a pregnancy registry of women with inborn errors
      of metabolism other than PKU. We will collect management plans, baseline laboratory values,
      prenatal and postpartum course including metabolic and obstetrical issues, and fetal/neonatal
      outcomes. This study will also investigate reproductive issues including infertility and use
      of artificial reproductive technologies. A registry of this type will allow physicians and
      patients to report varying management and outcomes, both positive and negative, with the
      broader goal of delineating optimal maternal and fetal outcomes for these unique patient
      populations. Our registry data would also serve as a vehicle to disseminate management
      experience for all providers, recognizing that individual centers may not have sufficient
      experience to make accurate management decisions on their own.
    

Observational model: Cohort
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Participants are women with inborn errors of metabolism who have been pregnant
      
Keywords: Inborn Error of Metabolism; Pregnancy; Amino acid disorder; Fatty acid oxidation disorder; Organic Acidemia; Natural History