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Recommendations for Maternal Phenylketonuria (PKU)

The American Academy of Pediatrics (AAP) recommends the following to manage maternal phenylketonuria (PKU):1

  • All women and girls of childbearing age with elevated phenylalanine (Phe) levels should be identified and counseled about the effects that high Phe may have on a fetus.
  • Pregnant women with high Phe levels should be offered tests to detect fetal problems.
  • A woman should have a blood test for PKU if her child has features that suggest the mother had high Phe levels during pregnancy. For example, her baby may be born with a very small head (microcephaly) and heart problems.

A woman who has PKU and is considering pregnancy or is pregnant should:

  • Achieve low levels (below 6 mg/dL) of Phe at least 3 months before conception.2
  • Get tested at least once a week.
  • Receive adequate nutrition.
  • Be offered genetic counseling before and during pregnancy.


  1. Committee on Genetics, American Academy of Pediatrics (2008). Maternal phenylketonuria. Pediatrics, 122(2): 445–449.

  2. Kaye CI, and the Committee on Genetics, American Academy of Pediatrics (2006, reaffirmed 2011). Phenylketonuria section of Newborn screening fact sheets: Technical report. Pediatrics, 118(3): e956–e957.

ByHealthwise Staff
Primary Medical ReviewerJohn Pope, MD - Pediatrics
Specialist Medical ReviewerChuck Norlin, MD, MD - Pediatrics
Last RevisedSeptember 8, 2011

WebMD Medical Reference from Healthwise

Last Updated: September 08, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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