ABSTRACT
Congenital malformations also known as birth defects are structural or functional abnormalities of prenatal origin which result from defective embryogenesis or an intrinsic defect in the developmental process. The birth prevalence of Congenital anomalies varies from country to country, and from region to region within the same country. The objective of this study was to determine the prevalence and spectrum of overt congenital anomalies in live born neonates in selected hospitals in the Kano metropolis of North Western Nigeria, as well as the associated maternal, paternal and neonatal risk factors. A descriptive study design was employed. All live born neonates in three major hospitals in Kano metropolis were prospectively studied from April 2013 to December 2013. Detailed family history and clinical data were recorded in a structured questionnaire for each child. Autopsies and cytogenetic analysis were not done. The congenital malformations were classified as multiple or single-system abnormalities. Of the 1456 live births which occurred during the study period, 41 had congenital malformations, giving a prevalence of 28.15 per 1000 live births. Five (12.20 %) had multiple malformations and 36 (87.80 %) had involvement of a single system. Of the neonates with multiple malformations, two had recognized syndromes. The most common systems involved in neonates with isolated single system malformations were the central nervous system (10 cases), the genitourinary system (10 cases), the dermatological system malformation (6 cases) and the gastrointestinal system (5 cases). The consanguinity rate in the study was 17.83 %. Although congenital malformations were more likely to occur in offspring from consanguineous marriages, this was however not statistically significant (p> 0.05). Birth weight of the neonates had a significant but negative association with the likelihood of being born with a congenital malformation [OR = 0.38; (95 % CI 0.20 - 0.71) p < 0.01]. Given the high frequency of central nervous system malformations in this study, the findings suggest that neural tube defects account for a significant proportion of congenital anomalies in the Kano metropolis. Also since the study showed that only 5 % of the mothers commenced use of folic acid containing multivitamin supplements in the first month of pregnancy or before conception, emphasis on the primary prevention of congenital malformations by encouraging peri-conceptional use of folic acid containing multivitamin supplements is recommended.