Some birth defects can be diagnosed before birth through ultrasound, amniocentesis, or chronic villus sampling (CVS). Most women have blood tests to screen for their risk of having a baby with a specific birth defect, such as Down syndrome and spina bifida. While it does not usually lead to a cure for the baby's birth defect, prenatal diagnosis can prepare the parents emotionally and help them prepare for a child with a birth defect. In other cases a birth defect is diagnosed after birth through physical examination or a blood test that screens for several disorders in newborns. A preconception examination, also known as a preconception visit, is one of the best ways to ensure a healthy pregnancy. The goals are to assess your overall health and identify any risk factors that can complicate a pregnancy. A preconception examination can include any of the following: A doctor will assess the medical history of both of your biological parents to see if any family member has had medical problems such as high blood pressure, diabetes, or mental retardation. A doctor will assess any possible genetic disorders that can be passed down to your child; some genetic disorders can be detected by blood tests before pregnancy. Personal Medical History: to determine if you have any medical conditions that may require special care during pregnancy (anemia, epilepsy, diabetes, high blood pressure); to gather information about previous surgeries; and to obtain information about past pregnancies such as complications, losses, and length of gestation. To assess immunity to diseases such as rubella (German measles) that can cause miscarriage or birth defects, a vaccine can be given at least three months prior to conception to provide immunity. Infection screening determines if a woman has a sexually transmitted infection, a urinary tract infection, or another type of infection that can be harmful to her or to the fetus. Most birth defects cannot be cured. Treatment focuses on managing the symptoms. In some cases, however, there are ways to treat specific birth defects. Gene therapy replaces a gene that is either missing or defective. Severe combined immunodeficiency diseases (SCID) are a group of very rare diseases for which gene therapy has been used. Enzymes are proteins for which genes code. So when a gene is mutated and does not produce the gene product, an enzyme is missing or defective. One way to treat this type of genetic defect is to replace the enzyme that the gene is not producing. An example of a condition for which enzyme replacement therapy has been developed is Gaucher disease. Some birth defects can be diagnosed and treated before birth. Prenatal surgery, for instance, can treat babies with urinary tract blockages and rare lung tumors.What is a preconception examination?
Family medical history
Genetic testing
Vaccination status
Infection screening
What are the treatment options for birth defects?
Gene therapy
Enzyme replacement therapy
Prenatal treatment
When pregnant women need medications, there’s often concern about possible effects on the fetus. Although some drugs are clearly recognized to cause birth defects (thalidomide being a notorious example), and others are generally recognized as safe, surprisingly little is known about most drugs' level of risk. Researchers in the Boston Children's Hospital Informatics Program (CHIP) have created a preclinical model for predicting a drug's teratogenicity (tendency to cause fetal malformations) based on characterizing the genes that it targets.
The model used bioinformatics and public databases to profile 619 drugs already assigned to a pregnancy risk class, and whose target genes or proteins — over 7,000 in all — are known. For each drug, CHIP investigators Asher Schachter, MD, MMSc, MS, and Isaac Kohane, MD, PhD, identified the number of targeted genes likely to be involved in fetal development, using telltale search terms like "genesis," "develop," "differentiate," or "growth." The drugs targeting a large proportion of genes associated with fetal development tended to be in the higher risk classes.
Based on the developmental gene profile, the researchers created a model that showed 79 percent accuracy in predicting whether a drug would be in Class A (safest) or Class X (known teratogen). "We can't provide a yes/no answer,” says Schachter, “but we found a pattern that can predict which are riskier."
Schachter and Kohane believe their model may be of interest to drug developers and prescribing physicians, and might provide useful information to incorporate in drug labeling. (Reproductive Toxicology, March 2011)
1. Steele MW, Breg WR. Chromosome analysis of human amniotic fluid cells. Lancet. 1966;1:383–385. [PubMed] [Google Scholar]
2. Chitayat D, Babul-Hirji R. Genetic counselling in prenatally diagnosed non-chromosomal fetal abnormalities. Curr Opin Obstet Gynecol. 2000;12:77–80. [PubMed] [Google Scholar]
3. Jenkins TM, Wapner RJ. First trimester prenatal diagnosis: chorionic villus sampling. Semin Perinatol. 1999;23:403–413. [PubMed] [Google Scholar]
4. Douglas Wilson R. Amniocentesis and chorionic villus sampling. Curr Opin Obstet Gynecol. 2000;12:81–86. [PubMed] [Google Scholar]
5. In: Fetal Abnormalities. Guidelines for Screeening, Diagnosis and Management. London, UK: RCPCH, RCOG; 1997. Royal College of Obstetricians and Gynaecologists, Royal College of Paediatrics and Child Health. Background evidence supporting the guidelines; p. 5. [Google Scholar]
6. Luck CA. Value of routine ultrasound scanning at 19 weeks: a four year study of 8849 deliveries. Br Med J. 1992;304:1474–1478. [PMC free article] [PubMed] [Google Scholar]
7. Romero R. Routine obstetric ultrasound. Ultrasound Obstet Gynecol. 1993;3:303–307. [PubMed] [Google Scholar]
8. Crane JP, LeFevre ML, Winborn RC, Evans JK, Ewingman BG, Bain RP, Frigoletto FD, McNellis D RADIUS Study Group. A randomised trial of prenatal ultrasonographic screening: Impact on the detection, management, and outcome of anomalous fetuses. Am J Obstet Gynecol. 1994;171:392–399. [PubMed] [Google Scholar]
9. Levine D, Barnes PD, Madsen JR, Abbot J, Tejas Meta T, Edelman R. Central nervous system abnormalities assessed with magnetic resonance. Obstet Gynecol. 1999;94:1011–1019. [PubMed] [Google Scholar]
10. Pilu G, Perolo A, Falco P, Visentin A, Gabrielli G, Bovicelli L. Ultrasound of the central nervous system. Curr Opin Obstet Gynecol. 2000;12:93–103. [PubMed] [Google Scholar]
11. Grandjean H, Larroque D, Levi S Eurofetus Study Group. The performance of routine ultrasonographic screening of pregnancies in the Eurofetus Study. Am J Obstet Gynecol. 1999;181:446–454. [PubMed] [Google Scholar]
12. Johnson P, Sebire NJ, Snijders RJM, Tunkel S, Nicolaides KH. Ultrasound screening for anencephaly at 10-14 weeks of gestation. Ultrasound Obstet Gynecol. 1997;9:14–16. [PubMed] [Google Scholar]
13. Chitty LS, Pandya PP. Ultrasound screening for fetal abnormalities in the first trimester. Prenat Diagn. 1997;17:1269–1281. [PubMed] [Google Scholar]
14. Sebire NJ, Noble PL, Thorpe-Beeston JG, Snijders RJ, Nicolaides K. Presence of the ‘lemon’ sign in fetuses with spina bifida at the 10-14-week scan. Ultrasound Obstet Gynecol. 1997;10:403–407. [PubMed] [Google Scholar]
15. Gembruch U. Prenatal diagnosis of congenital heart disease. Prenat Diagn. 1997;17:1283–97. [PubMed] [Google Scholar]
16. Rosendhal H, Kivinen S. Antenatal detection of congenital malformation by routine ultrasonography. Obstet Gynecol. 1989;73:947–51. [PubMed] [Google Scholar]
17. Lys F, Dewals P, Borlee Gremee I, Billeet A, Vincotte-Mols M, levi S. Evaluation of routine ultrasound examination for the prenatal diagnosis of malformation E. J. O.G. R.B. 1989;30:101–109. [PubMed] [Google Scholar]
18. Todros T, Viora E, Scali R. Diagnostica prenatale dei difetti congeniti. Predittività degli esami ecografici di primo livello. Atti LXVII Congresso Nazionale della Società Italiana di Ginecologia e Ostetricia. 1992 [Google Scholar]
19. Nicolaides KH, Azar G, Byrne D, Mansur C, Marks K. Fetal nuchal translucency:ultrasound screening for chromosomal defects in first trimester of pregnancy. Br Med. 1992;304:867–889. [PMC free article] [PubMed] [Google Scholar]
20. Souka AP, Snijders RJM, Novakov A, Soares W, Nicolaides KH. Defects and syndromes in chromosomally normal fetuses with increased nuchal translucency thickness at 10-14 weeks of gestation. Ultrasound Obstet Gynecol. 1998;11:391–400. [PubMed] [Google Scholar]
21. Spencer K, Souter V, Tul N, Snijders RJM, Nicolaides KH. A screening program for trisomy 21 at 10-14 weeks using fetal nuchal translucency, maternal serum free beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A. Ultrasound Obstet Gynecol. 1999;13:231–237. [PubMed] [Google Scholar]
22. Benacerraf B, Barss V, Laboda L. A sonographic sign for the detection in the second trimester of the fetus with Down's syndrome. Am J Obstet Gynecol. 1985;151:1078–1079. [PubMed] [Google Scholar]
23. Snijders RJM, Nicolaides KH. In: Ultrasound markers for fetal chromosome defects. Canforth, UK: Parthenon Publishing; 1996. Assessment of risks; pp. 63–120. [Google Scholar]
24. Benacerraf BR. Should sonographic screening for fetal Down syndrome be applied to low risk women? Ultrasound Obstet Gynecol. 2000;15:451–455. [PubMed] [Google Scholar]
25. Drugan A, Johnson MP, Evans MI. Ultrasound screening for fetal chromosome anomalies. Am J Med Genet. 2000;90:98–107. [PubMed] [Google Scholar]
26. Bahado-Singh RO, Oz AU, Kovanci E, Deren O, Copel J, Baumgarten A, Mahoney J. New Down syndrome screening algorithm: ultrasonographic biometry and multiple serum markers combined with maternal age. Am J Obstet Gynecol. 1998;179:1627–1631. [PubMed] [Google Scholar]
27. Viora E, Grassi Pirrone P, Bastonero S, Errante G, Sciarrone A, Campogrande M. Minor sonographic markers of fetal chromosomal anomalies: a review. It J Gynaecol Obstet. 1999;11:79–86. [Google Scholar]
28. Boyd PA, Chamberlain P, Hicks NR. 6-year experience of prenatal diagnosis in an unselected population in Oxford, UK. Lancet. 1998;352:1577–1781. [PubMed] [Google Scholar]
29. Filly RA. Obtetrical sonography: the best way to terrify a pregnant woman. J Ultrasound Med. 2000;19:1–5. [PubMed] [Google Scholar]
30. Todros T, Faggiano F, Chiappa E, Gaglioti P, Mitola B, Sciarrone A Gruppo Piemontese for Prenatal Screening of Congenital Heart Disease. Accuracy of routine ultrasonography in screening heart disease prenatally. Prenat Diagn. 1997;17:901–906. [PubMed] [Google Scholar]
31. Fesslova V, Nava S, Villa L Fetal Cardiology Study Group of the Italian Society of Pediatric Cardiology. Evolution and long term outcome in cases with fetal diagnosis of congenital heart disease: Italian multicentre study. Heart. 1999;82:594–549. [PMC free article] [PubMed] [Google Scholar]
32. Allan LD, Sharland GK, Milburn A, Lockhart SM, Groves AMM, Anderson RH, Cook AC, Fagg NL. Prospective diagnosis of 1,006 consecutive cases of congenital heart disease in the fetus. J Am Coll Cardiol. 1994;23:1452–1458. [PubMed] [Google Scholar]
33. Touati GD, Fermont L, Neveux JY, Vouhe PR, Gay F, Kachaner J. Effects of a systematic fetal detection on the outcome of severe congenital heart disease. Circulation. 1988;78:396. [Google Scholar]
34. Raymond FL, Simpson JM, Sharland GK, Mackie Ogilvie CM. Fetal echocardiography as a predictor of chromosomal abnormality. Lancet. 1997;350:930. [PubMed] [Google Scholar]
35. Paladini D, Calabro R, Palmieri S, D’Andrea T. Prenatal diagnosis of congenital heart disease and fetal karyotyping. obstet Gynecol. 1993;81:679–682. [PubMed] [Google Scholar]
36. Yates R. Fetal cardiac abnormalities and their association with aneuploidy. Prenat Diagn. 1999;19:563–566. [PubMed] [Google Scholar]
37. Paladini D, Rustico M, Todros T, Palmieri S, Gaglioti P, Russo MG, Chiappa E, D’Ottavio G. Conotruncal anomalies in prenatal life. Ultrasound Obstet Gynecol. 1996;8:241–246. [PubMed] [Google Scholar]
38. Klein SK, Cans C, Robert E, Jouk PS. Efficacy of routine ultrasound screening for congenital heart disease in Isere County, France. Prenat Diagn. 1999;19:318–322. [PubMed] [Google Scholar]
39. Buskens E, Grobbee DE, Frohn-Mulder IME, et al. Efficacy of routine fetal ultrasound screening for congenital heart disease in normal pregnancy. Circulation. 1996;94:67–72. [PubMed] [Google Scholar]
40. Stoll C, Alembik Y, Dott B, Meyer MJ, Pennerath A, Peter MO, De Geeter B. Evaluation of prenatal diagnosis of congenital heart disease. Prenat Diagn. 1998;18:801–807. [PubMed] [Google Scholar]
41. Hafner E, Scholler J, Schucter K, et al. Detection of congenital heart disease in a low-risk population. Prenat Diagn. 1998:808–815. [PubMed] [Google Scholar]
42. Todros T. Prenatal diagnosis and management of fetal cardiovascular malformations. Curr Opin Obstet Gynecol. 2000;12:87–92. [PubMed] [Google Scholar]
43. Gagliardi L, Todros T. Candiani G. B, Danesino V, Ostetricia Gastaldi A, editors. Le cardiopatie fetali. Principi di diagnosi e terapia. 1996:182–192. Masson, Milano. [Google Scholar]
44. Marden PM, Smith DW, McDonald MJ. Congenital anomalies in the newborn infant, including minor variations. J Pediatr. 1964;64:357–371. [PubMed] [Google Scholar]
45. Kalter H, Warkany J. Congenital malformations (first of two parts) N Engl J Med. 1983;308:424–431. [PubMed] [Google Scholar]
46. Kalter H, Warkany J. Congenital malformations (second of two parts) N Engl J Med. 1983;308:491–497. [PubMed] [Google Scholar]
47. Bonnet D, Coltri A, Butera G, Fermont L, Le Bidois J, Kachaner J, Sidi D. Detection of transposition of the great arteries in fetuses reduces neonatal morbidity and mortality. Circulation. 1999;99:916–918. [PubMed] [Google Scholar]
48. Kumar RK, Newburger JW, Gauvreau K, Kamenir SA, Hornberger LK. Comparison of outcome when hypoplastic left heart and transposition of the great arteries are diagnosed prenatally versus when diagnosis of these two conditions is made only postnataly. Am J Cardiol. 1999;83:1649–1653. [PubMed] [Google Scholar]
49. Daubeney PEF, Sharland GK, Cook AC, Keeton BR, Anderson RH, Webber SA. Pulmonary atresia with intact ventricular septum. Impact of fetal echocardiography on incidence at birth and postnatal outcome. Circulation. 1998;98:562–566. [PubMed] [Google Scholar]
50. Kern JH, Hayes CJ, Michler RE, Gersony WM, Quaegebeur JM. Survival and risk factor analysis for the Norwood procedure for hypoplastic left heart syndrome. Am J Cardiol. 1997;80:170–174. [PubMed] [Google Scholar]
51. Neilson JP. Ultrasound for fetal assessment in early pregnancy. The Cochrane Database of Systematic Reviews. 2000;2 [PubMed] [Google Scholar]
52. Zimmer EZ, Avraham Z, Sujoy P, Goldstein I, Bronshtein M. The influence of prenatal ultrasound on the prevalence of congenital anomalies at birth. Prenat Diagn. 1997;17:623–628. [PubMed] [Google Scholar]
53. Bull C. Current and potential impact of fetal diagnosis on prevalence and spectrum of serious congenital heart disease at term in the UK. Lancet. 1999;354:1242–1247. [PubMed] [Google Scholar]
54. Todros T, Presbitero P, Gaglioti P, Demarie D. Pulmonary stenosis with intact ventricular septum: documentation of development of the lesion echocardiographically during fetal life. Int J Cardiol. 1988;19:335–360. [PubMed] [Google Scholar]
55. AIUM Technical Bullettin. Performance of the basic fetal cardiac ultrasound examination. J Ultrasound Med. 1998;17:601–617. [PubMed] [Google Scholar]
56. Farina A, Malone FD, Bianchi DW. Fetal sonographic findings: analysis of the most frequent patterns and their specificity of association. Am J Med Genet. 2000;91:331–339. [PubMed] [Google Scholar]
57. Levine D, Barnes PD, Edelman RR. Obstetric MR imaging. Radiology. 1999;211:609–617. [PubMed] [Google Scholar]