Hospital-based birth defects surveillance: a guide to establish and operate

Birth defects (also called congenital anomalies) are defined as abnormalities of body structure or function that are present at birth and are of prenatal origin. Birth defects contribute to a significant proportion of perinatal, neonatal and child mortality.

Globally, about 7.9 million children are born annually with a serious birth defect of genetic or partially genetic origin, as per the estimates provided by March of Dimes Report (2006). WHO estimates that out of 1 million neonatal deaths in 2012 in the South-East Asia Region, about 46 000 (4.6%) were caused by birth defects.

The birth defects spectrum involves different organ systems, the most common being congenital heart diseases (CHD), neural tube defects (NTDs), a n d Down syndrome followed by hemoglobinopathies, musculoskeletal disorders and others. Many risk factors are known to be associated with birth defects such as genetic factors; maternal conditions, such as diabetes and obesity; maternal age; and behaviours and environmental exposures. The prevalence and spectrum of birth defects varies among different communities and regions depending on the presence or absence of these risk factors.

Since many of these factors are preventable, a wide range of preventive approaches are possible through legislation and policies. Some of the effective interventions are vaccination against rubella; folic acid supplementation; fortification of staple foods with micronutrients (iodine and folic acid); prevention and management of syphilis and diabetes in mother; controlling use of toxic chemicals; a timely identification of a family risk of inherited disease; and carrier screening with genetic counseling, etc.

Adequate data and information on birth defects is not available in many countries of the SouthEast Asia Region. Such information is important to understand the public health burden and to design prevention and management programmes in the country. To improve data and information, there is a need to develop surveillance mechanisms. In the Region, it has been considered to establish hospitalbased surveillance for birth defects to begin with, initially starting in selected hospitals with a high load of childbirths. In due course and with experience, this could be expanded to other hospitals, so that the data collected would be representative of most of the regions in the country. Later, population-based surveillance may be considered depending on availability of resources.