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:
- structural/metabolic;
- congenital infections; and
- 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 Defects | Estimated Incidence |
| Structural / Metabolic | |
| Heart and circulation | 1 in 115 births |
| Muscles and skeleton | 1 in 130 births |
| Club foot | 1 in 735 births |
| Cleft lip / palate | 1 in 930 births |
| Genital and urinary tract | 1 in 135 births |
| Nervous system and eye | 1 in 235 births |
| Anencephaly | 1 in 8,000 births |
| Spina bifida | 1 in 2,000 births |
| Chromosomal syndromes | 1 in 600 births |
| Down syndrome (Trisomy 21) | 1 in 900 births |
| Respiratory tract | 1 in 900 births |
| Metabolic disorders | 1 in 3,500 births |
| PKU | 1 in 12,000 births |
| Other | |
| Rh disease | 1 in 1,400 births |
| Fetal alcohol syndrome | 1 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 Unpublished review of the literature and information from various state and regional, birth defects surveillance systems (California, Iowa, Metropolitan Atlanta, New York,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).
