Global Health: Birth Defects and Disorders
27.07.2019
Birth defects, also known as congenital anomalies, are growing public health problems which cause structural and functional disorders that result in malformations, malfunctions or syndromes that may present in-utero or after birth. Birth defects cause significant morbidity and mortality with increase in health care expenditure and psychosocial problems for the child and family throughout life. It is the leading cause of infant mortality and occurs worldwide with about 3% live births. In general, different birth defects are existent in different rates in different parts of the world probably due to differences in distribution of risk factors.
In the early 1940s, scientists thought that genetic factors, which are out of the control of health workers, were the only predisposing factors to birth defects. However, the discovery that German measles affecting pregnant mothers led to birth defect showed that relevant public health measures could be put in place to reduce these disorders and defects. Shortly afterwards, it was also observed that the use of the sedative drug- thalidomide, by pregnant women led to increase in Amelia in embryos while the anti-acne drug, isotretinoin commonly known by its trade name Accutane causes oro-facial clefts. These findings showed that drugs could also lead to birth defects. Subsequently, the number of agents that cause birth defects- known as teratogens, continued to increase due to widespread surveillance, monitoring and observation. Other infectious causes include protozoans e.g. toxoplasmosis; bacteria e.g. syphilis; and viruses e.g. HIV. Besides drugs and infectious agents, birth defects can also be caused by exposure to environmental teratogens such as radiation and heavy metals or issues with maternal health such as obesity, diabetes, pregnancy before 18 years or after 35 years, smoking and substance abuse especially alcohol which causes foetal alcohol syndrome.
Although many birth defects, especially those of genetic origin, are difficult to treat or prevent, public health has focussed more on educating the public through awareness programmes on those that can be prevented. Several research studies worldwide have unequivocally demonstrated that increased folic acid intake (above the given FDA range) reduces the risk of neural tube defects. Public health officers also partner and work with the FDA to ensure that there is a black box warning against use of potential teratogens. More so, awareness is continuously created for other causes of birth defects such as radiation and poor hygiene or sanitation practices. Most awareness campaigns are targeted towards the prevention of infection and have proven to be effective in addressing some causes of birth defects. Screening and advanced testing such as karyotyping or PCR are essential to the diagnosis of genetic defects like Down syndrome as well as to counsel parents on what to expect. Stem cell research and gene therapy, on the other hand, continues to give hope to families of children with genetic disorders.