Fetal nuchal translucency scan in Nigeria

Olufemi Adebari Oloyede,Mkpe Abbey,Adeniyi Adebowale Oloyede,Onyinye Nwachukwu

doi:10.11604/pamj.2014.18.62.3291

Abstract

IntroductionTo evaluate the performance of first trimester nuchal translucency scan screening among pregnant women in Nigeria.MethodsA prospective observational and questionnaire based study involving 510 pregnant women between 11+0 and 13+6 weeks. Routine counselling and nuchal translucency measurement was conducted using the FMF, London guidelines. Chorionic villous sampling was done at NT ≥ 2.5 mm or ≥ 95th centile.ResultsFive hundred and ten out of 542 (94.1%) were analysed, mainly referred by health care workers (87.2%) and from predominantly private facilities (94.3%). The number of NT scans performed increased in successive years with corresponding decrease in the mean scanning time. Scan was successfully completed at first attempt in (96.5%), with mean scanning time of 28.3 minutes. Nuchal translucency increases with gestational but not maternal age. The median and 95th centile at 11+0 week was 1.2mm and 1.7 mm and at 13+6 weeks was 1.5 mm and 2.2 mm. Using a cut-off of ≥ 2.5 mm or ≥ 95th centile, 17 (3.3%) screened positive. Three out of the 17 had invasive testing and 2 (DR = 66.7%) were confirmed trisomy 21, with a false positive rate of 5.9%. Although majority (86.4%) were willing to have invasive testing, only few (3 or 17.6%) of the high risk group had testing.ConclusionThe study demonstrated that NT scan is feasible as a screening tool in pregnancy in Nigeria. Measures of improving utilization include wider dissemination of information, provision of dedicated NT clinics and manpower training.

Highlights

To evaluate the performance of first trimester nuchal translucency scan screening among pregnant women in Nigeria
The aim of the present study was to report on the performance of routine nuchal translucency scan, assess its relationship with maternal and gestational age in Nigeria as well as the detection and false positive rates for Down syndrome
We studied data from 510 women who attended Fetal Medicine and Genetic diagnosis centre between January 2007 and December 2012 for antenatal screening for Down syndrome using the nuchal translucency scan

Summary

Introduction

To evaluate the performance of first trimester nuchal translucency scan screening among pregnant women in Nigeria. Nuchal translucency (NT) has found useful application as an antenatal screening marker for chromosomal abnormalities in the late first trimester of pregnancy [1,2,3] As a routine, it provides a first trimester detection rate of about 80% for Down syndrome pregnancies for a false positive rate of about 5%, and even superior detection rates for trisomy 13 and 18 [2,3,4]. Similar to any other new service, its utilization and performance can be affected by numerous factors ranging from manpower, facilities, safety and perceived outcome

Objectives

Methods

Results

Discussion

Conclusion