Investigations of Visible Congenital Anomalies at Birth and Associated Factors in Southwestern Ethiopia
No Thumbnail Available
Date
2021-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Abeba University
Abstract
Background: Prenatal development can be considered as normal or abnormal. Abnormal
development occurs because of interference of normal development from genetic disorders,
environmental factors or the combination of genetic and environmental factors during the
critical period of embryogenesis with which the neonate is born with a disorder that is described
as congenital anomalies. Congenital anomaly is a series of structural, functional and metabolic
abnormalities present at birth because of several causative agents during critical period of
intrauterine life.
Congenital anomalies highly contribute to abnormal intrauterine development that leads to
prenatal disturbance and postnatal morphological defects that may persist throughout life.
According to World Health Statistics, about 260,000 neonatal deaths worldwide are caused by
congenital anomalies. The frequency of congenital anomalies in developing countries including
Ethiopia is underestimated because of the deficiencies in diagnostic capabilities and lack of
reliability of medical records and health statistics. Instead, the available recorded diagnoses in
vital health statistics relay on obvious illnesses, rather than on preexisting congenital anomaly
present at birth contributing to infant mortality and morbidity leading to the significant
community problem. Therefore, it is vital to evaluate types, prevalence, incidence and
predisposing risk factors which may provide a baseline for public health plan, suggesting
protective strategies against congenital anomalies and establish genetic counseling if the defects
are of genetic origin and provide input for further investigation.
Objective: To assess the prevalence, incidence, types, and patterns of congenital anomalies
or disorder at birth and associated risk factors among newborns in southwestern Ethiopia
Methods and materials: The study was conducted in southwestern Ethiopia. This research
used quantitative study methods and genetic analysis. The quantitative methods included
institution based retrospective cross-sectional, descriptive cross-sectional and case-control
study. The study was conducted from 2011 to 2015 during which 45,951 deliveries were
attended for the retrospective document review study. All records of births that occurred in the
selected hospitals during the study period were identified from medical records. Descriptive cross sectional study was also conducted in those six selected hospitals from 2016 to 2018,
during which 35,080 deliveries were attained. A prospective registration of all delivers of any
gestational age during the study period was conducted to determine the incidence of congenital
anomalies. Newborns either still or life birth was evaluated for the presence of any congenital
anomalies. Data was collected using structured and standard checklist. Case-Control study was
conducted on newborns and their mothers within the period of 2016 to 2018 in those selected
hospitals. Data were collected after evaluation of the neonate for the presence of congenital
anomalies using the standard pretested checklist. The data was analyzed using SPSS version
25.0. P <0.05 was set to be statistically significant. Chromosomal abnormities were also
detected in their sub telomeres region using multiple ligation probe dependent amplifications
method with help of probe mix.
Results
The prevalence of the birth defects at birth was found to be 5.5 per 1000 births. Of a total of
35,080 neonates delivered during the study period, 0.72% of them had congenital anomalies.
The overall incidence of congenital anomalies in southwestern Ethiopia was 71.6 per 10,000
births. Risk factors such as unidentified use of medications or drugs in the first three months of
pregnancy (AOR = 3.435; 95% CI: 2.286 – 5.160), exposure to pesticide (AOR = 3.926; 95%
CI: 1.659 – 9.289), passive smoking (AOR = 4.104; 95% CI: 2.277 – 7.397), surface water as
sources of drinking (AOR = 2.073; 95% CI: 1.385 – 3.100) were significantly associated with
the occurrence of congenital anomalies. Similarly, risk factors such as passive smoking (AOR
= 4.171; 95% CI: 2.272 – 7.681), exposure to pesticide (AOR = 3.823; 95% CI: 1.606 – 9.106),
and maternal diabetes mellitus (AOR = 16.381; 95% CI: 1.614 – 166.241) were significantly
associated with the occurrence of neural tube defects. Multiple ligation dependent probe
amplification analysis confirmed the presence of deletion in the chromosome bands of 3q29,
8q24.3, 9q34.4, 15q11.2, 15q26.3, 18p11.32, 19q13.43, Xq28 and duplications of 3p26.3 and
6p25.3 in sample population tested for chromosomal abnormalities
Conclusions
Nearly equal proportions of birth defects occurred among male and female newborns. The most
frequent congenital anomaly was neural tube defects followed by musculoskeletal defects. From
frequency distribution of associated factors, mothers who had neonates with congenital
anomalies were exposed to passive smoking, pesticides, unidentified usage of medicines during
the first three months. Poor folic acid supplementation was more frequent among the neonates
delivered with congenital anomalies. Risk factors such as passive smoking, exposure to
pesticides, chemicals and use of surface water as a source of drinking during early pregnancy
had a significant association with the occurrences of congenital anomalies. As the congenital
anomalies were found to be the main causes of infant mortality and morbidity, there is a need
for an urgent intervention to control the cases and there is a need to continuously provide health
information for the community on how to prevent and control predisposing risk factors.
Chromosomal abnormalities were evident in sub-telemeric regions of some sample population.
Description
Keywords
Birth, Prenatal development