Genetic Epidemiology of Congenital Malformations in Neonates Born at Teaching Hospitals in North West Nigeria

Congenital malformations are a significant cause of neonatal mortality and childhood disability in Nigeria, with both genetic and environmental contributors. Population-specific genetic epidemiology data on congenital malformations are critically needed to guide prevention and management strategies. This study determined the prevalence, pattern, and genetic correlates of congenital malformations in neonates born at teaching hospitals in Kano, Kaduna, and Sokoto States, North West Nigeria. A prospective observational study enrolled all liveborn neonates over a 12-month period at three teaching hospitals, identifying those with major structural malformations on clinical examination. Chromosomal analysis using karyotyping was performed on all malformed neonates and their parents. Risk factor data including parental age, consanguinity, periconceptional folic acid use, and teratogen exposure were collected. The prevalence of congenital malformations was documented alongside organ system distribution. Chromosomal abnormalities accounted for approximately 30 percent of identified malformations, with trisomy 21 (Down syndrome) predominating. Consanguinity was significantly associated with the occurrence of malformations. Deficient periconceptional folic acid use was common among mothers of affected neonates. These findings advocate for antenatal chromosome screening and folic acid supplementation campaigns in North West Nigeria. Keywords: congenital malformations, neonatal, chromosomal abnormalities, North West Nigeria, karyotyping