Background: Estimates of the proportion of birth defects diagnosed before birth exist for only a few types of birth defects and for a few geographic regions in the United States. This population-based study examines rates of prenatal diagnosis for previously unstudied birth defects in a new geographic region. Methods: Active surveillance of 23 categories of birth defects among 111,902 infants born in 77 birthing hospitals in Texas in 1995 identified 852 infants or fetuses with major birth defects. Surveillance was conducted by the Texas Birth Defects Monitoring Program of the Texas Department of Health. Two regions were covered, the Houston/Galveston metropolitan area as well as the Lower Rio Grande Valley of Texas. Rates of prenatal diagnosis were evaluated for 23 different types of birth defects, using proportions and 95% confidence intervals. Results: One third of the 852 infants or fetuses with birth defects were prenatally diagnosed. Diagnosis rates varied greatly depending on the type of birth defects and were lower among infants born to Black and Hispanic women. More than 60% of anencephaly, encephalocele, gastroschisis and trisomies 13 and 18 were diagnosed antenatally. Many of the fetuses that were electively terminated had birth defects or combinations of birth defects that were potentially lethal. Prevalence rates for birth defects generally do not include fetuses that die or are electively terminated before 20 weeks of gestation. Thus, 36% of anencephaly, 21% of omphalocele, 15% of encephalocele and between 7 and 10% of spina bifida, hydrocephaly, renal agenesis, and trisomies 13, 18, and 21 were not included in our published rates. Conclusions: Published rates for specific types of birth defects are spuriously low. This should be considered when investigating alleged clusters and comparing rates of birth defects across geographic areas. Since many elective abortions are for lethal or potentially lethal birth defects, a major effect of prenatal diagnosis is the resultant decrease in infant mortality attributable to birth defects.
© 2000 S. Karger AG, Basel
D. Kim Waller, PhD, Assistant Professor of Epidemiology
University of Texas Houston Health Science Center
School of Public Health, 1200 Hermann Pressler Drive, W-210
Houston, TX 77225 (USA)
Tel. +1 713 500 9155, Fax +1 713 500 9149, E-Mail email@example.com
Received: Received: October 15, 1999
Accepted: March 16, 2000
Number of Print Pages : 7
Number of Figures : 2, Number of Tables : 2, Number of References : 20
Fetal Diagnosis and Therapy (Clinical Advances and Basic Research)
Formerly ‘Fetal Therapy’
Official Organ of the ‘International Fetal Medicine, Surgery Society’ and the International Society ‘Fetus as a Patient’
Vol. 15, No. 6, Year 2000 (Cover Date: November-December 2000)
Journal Editor: W. Holzgreve, Basel
ISSN: 1015–3837 (print), 1421–9964 (Online)
For additional information: http://www.karger.com/journals/fdt
Article / Publication Details
Published online: 12/1/2000
Issue release date: November–December 2000
Number of Print Pages: 7
Number of Figures: 2
Number of Tables: 2
ISSN: 1015-3837 (Print)
eISSN: 1421-9964 (Online)
For additional information: http://www.karger.com/FDT
Copyright / Drug Dosage
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in goverment regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.