CORREA–VILLASE ˜NOR ET AL.
fects or defect combinations for a specified time. Expected numbers are obtained from baseline prevalence data for the previous 2 years. The CUSUM technique (Lucas, ‘85) is used to signal statistically significant changes in birth de- fects rates. Follow-up studies are conducted on occasion when appropriate.
lance programs. Using MACDP as a basis, the National Birth Defects Prevention Network (NBDPN) was formed and now has 40 state birth defect surveillance programs as members. This network publishes annual reports on the prevalence of birth defects in approximately one-half of the U.S. birth population (NBDPN, ’00, ‘01, ‘02).
MACDP provides reports on rates of birth defects to local and state officials and international programs on a regular basis. These include reports to the National Birth Defects Prevention Networks and to the International Clearinghouse for Birth Defects Monitoring Systems, an international consortium of 35 birth defects programs (ICBD, ‘02). MACDP is currently developing a more de- tailed technical report on birth defects rates for regular dissemination to local and state officials. Routine compila- tion of rates and reports of temporal trends and regional variations can be useful to health-care providers and to local and state officials.
MACDP data have allowed the conduct of studies on the descriptive epidemiology of birth defects, evaluation of potential teratogenic exposures, and examination of possible etiologic factors contributing to birth defects (Table 2).
MACDP served as the source of data on babies born with major structural birth defects for the Atlanta Birth Defects Case-Control (ABDCC) Study (Erickson et al., ‘84). Results from that study of births occurring during 1968- 1980 led to the conclusion that there was no strong evi-
During its 35 years of operation, MACDP has made several contributions to birth defects surveillance, epide- miology, and prevention.
MACDP has been collecting, analyzing, and interpreting birth defects surveillance data on an ongoing basis, and has identified almost 40,000 babies with serious birth defects. MACDP has served as a prototype for active case ascer- tainment surveillance systems across the United States and in many other countries, and as a model for surveillance programs for other adverse reproductive outcomes, such as developmental disabilities (Metropolitan Atlanta Devel- opmental Disabilities Surveillance Program [MADDSP]) and fetal alcohol syndrome (Fetal Alcohol Syndrome Sur- veillance Network [FASSNet]).
MACDP has developed tools and methodology to sup- port birth defect surveillance in the United States and worldwide (Edmonds et al, ’81). MACDP has defined sur- veillance procedures for birth defect case ascertainment and validation and worked towards developing a standard coding format for use in birth defect programs (Oakley, ’84; Lynberg et al., ’93).
MACDP has been documenting long-term trends in a number of defects (CDC, ’79, ’81), such as declines in the rates of neural tube defects before the widespread use of prenatal diagnosis and food fortification with folic acid (Yen et al., ‘92) (Figure 2), increasing rates of hypospadias (Paulozzi et al., ‘97), and increasing rates of heart defects (Figure 3) (Botto et al., ’01). Surveillance data from MACDP have been used to address important public health issues, such as a decline in congenital rubella syn- drome with the decline in prevalence of maternal rubella (Cochi et al., ’89), and the impact of prenatal diagnosis and new diagnostic techniques on birth defect rates (Roberts et al., ‘95). MACDP data have been essential in assisting state health departments in their response to public concerns about apparent clusters of birth defects and in serving as baseline rates in comparison studies of birth defects fre- quencies in special populations, such as pregnant women taking specific medications (Safra and Oakley ‘75, ‘76) and Gulf War veterans (Araneta et al, ’97).
dence to support the position that Vietnam veterans had a greater risk than other men of fathering babies with serious birth defects. Other analyses from this large database have greatly increased understanding of risk factors associated with birth defects, such as prescription medications (Safra & Oakley, ‘75, ‘76), cocaine abuse (Chavez et al., ‘89), maternal rubella (Cochi et al., ‘89), maternal diabetes mel- litus (Becerra et al., ‘90), obesity (Watkins et al., ‘96, ‘01), febrile illnesses (Lynberg et al., ‘94; Botto et al., ‘01), vita- min A use (Khoury et al., ‘96), alcohol use (Moore et al., ‘97), maternal smoking (Honein et al., ‘00), and the effect modification of maternal diabetes by multivitamins (Cor- rea et al., 03).
MACDP served as a source of case data for the Atlanta Birth Defects Risk Factors Surveillance project, a case-con- trol study of birth defects that served as a precursor to the National Birth Defects Prevention Study (NBDPS). The NBDPS is a multicenter case-control study of genetic and environmental risk factors for birth defects that currently has collected data on 10,000 case and control infants (Yoon et al., ‘01). MACDP also serves as a source of case data for a collaborative study of risk factors for Down syndrome with Emory University School of Medicine (Yang et al., ‘99).
More recently, MACDP data have been linked with the National Death Index and Georgia vital statistics. This linkage has allowed two recent population-based studies of the survival experience of and prognostic factors for children with spina bifida (Wong and Pau- lozzi, ‘01) and encephalocele (Siffel et al., ’03) in recent years.
Data from the MACDP-based ABDCC Study corrobo- rated initial studies (Smithells et al., ‘80, ‘83) that found a reduced risk for NTDs in the offspring of mothers who used periconceptional multivitamins (CDC, ’88; Mulinare et al., ‘88). This and other studies (Milunsky et al., ’89; Bower et al., ’89) supported the implementation of ran- domized controlled trials of folic acid (MRC, ‘91) that ultimately led to the 1992 U.S. Public Health Service rec- ommendation for folic acid consumption in women of childbearing age (CDC, ‘92), and to mandatory food forti- fication in 1998 (FDA, ‘96). Data from the Beijing Medical
Through the use of cooperative agreements, CDC has supported the development of state birth defect surveil-
University-CDC community intervention
project in adapted
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