Survey of prenatal screening policies in Europe for structural malformations and chromosome anomalies, and their impact on detection and termination rates for neural tube defects and Down’s syndrome

Pa Boyd,B Khoshnood,H Dolk,C Devigan,E Garne,M Loane,Eurocat Working Group

doi:10.1111/j.1471-0528.2008.01700.x

Abstract

ObjectiveTo ‘map’ the current (2004) state of prenatal screening in Europe.Design(i) Survey of country policies and (ii) analysis of data from EUROCAT (European Surveillance of Congenital Anomalies) population-based congenital anomaly registers.SettingEurope.PopulationSurvey of prenatal screening policies in 18 countries and 1.13 million births in 12 countries in 2002–04.Methods(i) Questionnaire on national screening policies and termination of pregnancy for fetal anomaly (TOPFA) laws in 2004. (ii) Analysis of data on prenatal detection and termination for Down's syndrome and neural tube defects (NTDs) using the EUROCAT database.Main outcome measuresExistence of national prenatal screening policies, legal gestation limit for TOPFA, prenatal detection and termination rates for Down's syndrome and NTD.ResultsTen of the 18 countries had a national country-wide policy for Down's syndrome screening and 14/18 for structural anomaly scanning. Sixty-eight percent of Down's syndrome cases (range 0–95%) were detected prenatally, of which 88% resulted in termination of pregnancy. Eighty-eight percent (range 25–94%) of cases of NTD were prenatally detected, of which 88% resulted in termination. Countries with a first-trimester screening policy had the highest proportion of prenatally diagnosed Down's syndrome cases. Countries with no official national Down's syndrome screening or structural anomaly scan policy had the lowest proportion of prenatally diagnosed Down's syndrome and NTD cases. Six of the 18 countries had a legal gestational age limit for TOPFA, and in two countries, termination of pregnancy was illegal at any gestation.ConclusionsThere are large differences in screening policies between countries in Europe. These, as well as organisational and cultural factors, are associated with wide country variation in prenatal detection rates for Down's syndrome and NTD.Please cite this paper as: Boyd P, DeVigan C, Khoshnood B, Loane M, Garne E, Dolk H, and the EUROCAT working group. Survey of prenatal screening policies in Europe for structural malformations and chromosome anomalies, and their impact on detection and termination rates for neural tube defects and Down's syndrome. BJOG 2008;115:689–696.

Highlights

Over the past 20 years, there have been major advances in the field of prenatal screening for Down’s syndrome and in the efficacy of ultrasound scanning for the detection of fetal anomalies
Eighty-eight percent of cases of neural tube defects (NTDs) were prenatally detected, of which 88% resulted in termination
Six of the 18 countries had a legal gestational age limit for termination of pregnancy for fetal anomaly (TOPFA), and in two countries, termination of pregnancy was illegal at any gestation

Summary

Introduction

Over the past 20 years, there have been major advances in the field of prenatal screening for Down’s syndrome and in the efficacy of ultrasound scanning for the detection of fetal anomalies. Offering an amniocentesis to the oldest 5% of women identified about 30% of pregnancies with Down’s syndrome.[1] Today, a number of different noninvasive screening tests, which can be offered to women of any age, are available. These tests have different detection and false-positive rates.[2,3,4]. A variety of national policies or recommendations concerning prenatal screening and diagnostic testing for Down’s syndrome and ultrasound screening for structural anomalies have been developed in different countries and areas within countries. Termination of pregnancy is a controversial subject in many countries, and the laws governing it and legal gestation limits vary

Methods

Results

Discussion

Conclusion