Antenatal and postnatal diagnoses of visible congenital malformations in a sub-Saharan African setting: a prospective multicenter cohort study

BACKGROUND: Visible congenital malformations (VCMs) are one of the principal causes of disability in the world. Prenatal diagnosis is a paramount mandatory integral part of the follow up of pregnancies with VCM of the foetus in high-income setting. We aimed to determine the incidence of prenatal diagnosis of VCMs in a low-resource setting with no policy on antenatal diagnosis of VCMs. METHODS: We carried out a prospective cohort multicenter study from July 2015 to June 2016 in 10 randomly selected maternity units of Yaoundé, Cameroon. We enrolled all newborns with one or more detectable VCMs at birth. Variables studied were findings of the 1st, 2nd and 3rd trimesters’ obstetrical ultrasound scans, in order to establish a concordance between the clinical and sonographic diagnoses of the VCMs and determine the frequency of antenatal diagnosis as well as the rate of medical abortion. RESULTS: The incidence of VCMs was 9 per 1000 births. The main VCMs were malformations of the skeletal (4.3%), neurological (2.2%), and gastrointestinal (2.1%) systems. The sex ratio was 1.1. Among the malformed newborns, 37% were premature and in 18.5% the diagnosis of a VCM was confirmed after a therapeutic termination of pregnancy (following suggestive findings of a malformation on antenatal ultrasound scan). The prevalence of sonographic antenatal diagnosis of VCMs was 21%. Hydrocephalus was the most diagnosed VCM antenatally. The mean gestational age at which antenatal clinics were initiated was 15 ± 5 weeks. The mean number of obstetrical ultrasound scans performed was two. CONCLUSION: The incidence of VCMs in our resource-limited setting is high and antenatal diagnosis rates are very low. Overall, our study emphasizes on the importance antenatal diagnosis of VCMs, often overlooked in our setting. The goal being to reduce maternal and foetal morbidity in a setting already burdened by a high maternal and neonatal mortality.