Including prenatal diagnoses in birth defects monitoring: Experience of the Metropolitan Atlanta Congenital Defects Program§††‡‡


  • Janet D. Cragan,

    Corresponding author
    1. Division of Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
    • Centers for Disease Control and Prevention, MS E-86, 1600 Clifton Rd NE, Atlanta, GA 30333
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  • Suzanne M. Gilboa

    1. Division of Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

  • Presented, in part, at the 8th Annual Meeting of the National Birth Defects Prevention Network, January 24–26, 2005, Scottsdale, Arizona.

  • §

    Portions of the data related to Down syndrome; anencephaly, spina bifida, and encephalocele; and trisomies 13 and 18 appear in the following publications:

  • Siffel C, Correa A, Cragan J, Alverson CJ. Prenatal diagnosis, pregnancy terminations and prevalence of Down syndrome in Atlanta. Birth Defects Res A Clin Mol Teratol. 2004 Sep;70(9):565–71.

  • Rowland CA, Correa A, Cragan JD, Alverson CJ. Are encephaloceles neural tube defects? Pediatrics. 2006;118:916–23.

  • ††

    Crider KS, Olney RS, Cragan JD. Trisomies 13 and 18: Population Prevalences, Characteristics, and Prenatal Diagnosis, Metropolitan Atlanta, 1994-2003. Am J Med Genet A. 2008;146(7):820–6.

  • ‡‡

    This article is a US Government work and, as such, is in the public domain in the United States of America.


BACKGROUND: Advances in prenatal diagnosis have led to changes in the management of pregnancies affected with birth defects. These changes pose unique challenges for birth defects monitoring programs which use hospital-based sources. METHODS: In 1994, Metropolitan Atlanta Congenital Defects Program (MACDP) abstractors began to visit area perinatologists' offices to identify pregnancies diagnosed prenatally with fetal defects. These pregnancies were then linked with existing MACDP cases and the hospital deliveries abstracted. Those without a hospital delivery were included as having unknown outcomes. Prenatally diagnosed defects were classified as definite or possible based on the certainty of the prenatal description. For 1995–2004, we calculated minimum and maximum adjusted defect prevalences by adding definite prenatal defects, and definite plus possible prenatal defects, to the hospital-based cases. RESULTS: We identified 1009 pregnancies with a prenatally diagnosed defect not ascertained from MACDP hospital sources. Including these increased the total defect prevalence from 28 per 1000 live births to a minimum of 29.94 (6.9% increase) and maximum of 30.14 (7.7% increase) per 1000. The minimum increase was greater than 50% for conjoined twins, triploidy, craniorachischisis, cystic hygroma, Klinefelter syndrome, anencephaly, Turner syndrome, and trisomies 13, 18 and 21 among mothers ≥35. CONCLUSIONS: These data reflect the variety of congenital abnormalities that can be detected prenatally and the importance of including prenatal diagnoses in birth defects monitoring data. Birth defects monitoring programs should assess individually the extent to which prenatal diagnosis can affect the accuracy and completeness of their data. Birth Defects Research (Part A), 2009. Published 2008 Wiley-Liss, Inc.