Prevalence and Outcome of Increased Nuchal Translucency in Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria: A Cohort Study

Abstract

Background: An important component of the first‑trimester scan is nuchal translucency thickness at 11 weeks to 13 weeks 6 days of gestation. A nuchal translucency ≥3.3 mm is a significant early pregnancy scan finding associated with Trisomies 13, 18, and 21 and congenital heart diseases. Aims: To determine the prevalence and outcome of increased fetal nuchal translucency among pregnant women. Subjects and Methods: A prospective cohort study at the Obstetrics and Gynaecology Department of Usmanu Danfodiyo University Teaching Hospital Sokoto. This was a prospective study of 265 consecutively recruited women in the first trimester of pregnancy who presented to antenatal clinics over a 20‑week period. An NT scan was conducted at 11 weeks to 13 weeks 6 days followed by an anomaly scan at 18–22 weeks. Patients were followed up to delivery and 6‑week post‑partum. The neonates were examined at delivery and at 6‑week postnatal life. Data entry and analysis was done with IBM SPSS version 20. The level of significance was set at less than 0.05. Frequency distribution; student t‑test and Chi‑squared test. Results: The 95th percentile NT was 3.3 mm and the prevalence of increased  NT above 3.3 mm was 3%. The mean maternal age of the participants was
28.1 ± 5.1 years and the modal parity was Para 0. The most common anomalies associated with increased NT were ventricular septal defect and spina bifida. A congenital anomaly was significantly associated with increased NT (P <0.001). Conclusions: The prevalence of increased fetal nuchal translucency is relatively high in our environment and is associated with congenital fetal defects. Routine screening with first‑trimester ultrasound will help detect congenital anomalies early.