Developmental Biology

Table 1

Leading Categories of Birth Defects

The estimated incidences for the leading categories of birth defects are provided in the table below. Birth defects are grouped into three major categories:

  1. structural/metabolic;
  2. congenital infections; and
  3. other conditions.

Birth defects of the heart and circulatory system affect more infants than any other type of birth defect. Of all infants born each year, approximately 1 in 115 has heart and/or circulatory defects.

Birth DefectsEstimated Incidence
Structural / Metabolic 
Heart and circulation1 in 115 births
Muscles and skeleton1 in 130 births
Club foot1 in 735 births
Cleft lip / palate1 in 930 births
Genital and urinary tract1 in 135 births
Nervous system and eye1 in 235 births
Anencephaly1 in 8,000 births
Spina bifida1 in 2,000 births
Chromosomal syndromes1 in 600 births
Down syndrome (Trisomy 21)1 in 900 births
Respiratory tract1 in 900 births
Metabolic disorders1 in 3,500 births
PKU1 in 12,000 births
 
Other
Rh disease1 in 1,400 births
Fetal alcohol syndrome1 in 1,000 births

Sources: March of Dimes Perinatal Data Center, 2000. Unpublished review of the literature and information from various state and regional, birth defects surveillance systems (California, Iowa, Metropolitan Atlanta, New York, and Texas).