Birth Defect Cases and Case Rates

In the years 2007 and 2008, there were 9,570 and 9,202 cases of birth defects reported for children under one year of age, respectively. The rate for either year was about 770 cases per 10,000 resident live births. For the same children born during 2007, there were an additional 1,507 cases reported for children of two years of age. This translates into a prevalence rate of 896.3 cases per 10,000 resident live births. Starting in 2000, significant efforts to improve reporting quality and completeness were initiated and the prevalence rate for two-year olds based upon reported cases has been above 800 per 10,000 for the past five years. (See Birth Defects Cases and Case Rates.)

Infant Death Rates

The infant death rate for children born in 2008 with a reportable birth defect is 35.1 per 1,000. This compares to an infant death rate of 7.4 per 1,000 for all resident infants born in Michigan during 2008. The relative risk of infant mortality among children with a birth defect was 7 in 2008. Birth defect rates were higher in 2008 than in 2007, while infant mortality rates were lower; specifically 31.2 for children with birth defects and 8.8 for all children in 2007. (See Mortality Rates Among Children.)

Mortality Risk

A higher mortality risk can be expected for children with birth defects well beyond the first year of life. The cumulative mortality rate for resident children under 2 years of age born during 2007 was 8.8 per 1,000. Children born during 2007 with a birth defect had a cumulative mortality rate of 31.2 per 1,000 by the end of the second year of life. The mortality rate differential remains high throughout early childhood. For deaths under the age of 17 years, the experience of children born in 1992 indicates death rates of 72.2 per 1,000 for children with birth defects and 14.4 per 1,000 for children generally. The significantly higher mortality rate for children with birth defects underscores the seriousness of these conditions. (See Cumulative Mortality Among Children.)

Birth Defects By Diagnostic Code Groups

The most common diagnostic category reported in 2008 involves anomalies of the heart and circulatory system. Conditions affecting the musculoskeletal system are the next most commonly reported and anomalies of the genital and urinary systems are third. (See Birth Defects by Diagnostic Code Group by Birth Year.) With regard to mortality, the number of deaths was highest in 2008 for children with heart and circulatory anomalies, followed by deaths to children with respiratory anomalies, with central nervous system anomaly associated deaths third highest. Similiarly, infant mortality rates are highest for the chromosomal anomalies, central nervous system anomalies and then respiratory anomalies, based upon mortality among the 2006-2008 birth cohorts. (See Infant Deaths to Michigan Children with Reported Birth Defects and Mortality Rates.)

Tables describing detailed condition information are also provided.

There are three potential sources of error in these data, especially at the county level: