Is fetal anatomic assessment on follow-up antepartum sonograms clinically useful?
OBJECTIVE
The purpose of this study was to evaluate the clinical usefulness of a fetal anatomic survey on follow-up antepartum sonograms.


METHODS
A retrospective follow-up study was conducted at a low-risk maternity clinic from July 1, 2005, to June 30, 2006. Eligible women had at least 1 prior sonographic examination beyond 18 weeks' gestation with a complete and normal fetal anatomic assessment and at least 1 follow-up sonogram. Full fetal anatomic surveys were performed on all follow-up sonograms regardless of the indication. Neonatal charts were reviewed for those patients whose follow-up sonograms revealed unanticipated fetal anomalies. Neonatal intervention was defined as surgical or medical therapy or arranged subspecialty follow-up specifically for the suspected fetal anomaly.


RESULTS
Of a total of 4269 sonographic examinations performed, 437 (10.2%) were follow-up studies. Of these, 101 (23.1%) were excluded because the initial sonogram revealed a suspected fetal anomaly, and 42 (9.8%) were excluded for other reasons. Of the remaining 294 women, 21 (7.1%) had an unanticipated fetal anomaly, most often renal pyelectasis. Compared with follow-up sonography for other reasons, repeated sonography for fetal growth evaluation yielded a higher incidence of unexpected fetal anomalies: 15 (12.3%) of 122 versus 6 (3.5%) of 172 (P = .01). When compared with the neonates in the nongrowth indications group, those neonates whose mothers had sonographic examinations for fetal growth had a higher rate of neonatal interventions: 6 (40.0%) of 15 versus 0 (0%) of 6 (P = .04).


CONCLUSIONS
A fetal anatomic survey on follow-up sonograms may identify unanticipated fetal anomalies, especially when the indication is for fetal growth.
Toy
Eugene C
EC
Department of Obstetrics and Gynecology, The Methodist Hospital, 1819 Crawford St, Suite 1708, Houston, TX 77002 USA. ectoy@tmhs.org
Montealegre
Alvaro I
AI
Fernandez
Laura P
LP
Harms
Konrad P
KP
Kaplan
Alan L
AL
D000328:Adult; D016009:Chi-Square Distribution; D000013:Congenital Abnormalities / Q000000981:diagnostic imaging*; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D005500:Follow-Up Studies; D005865:Gestational Age; D006801:Humans; D049590:Postpartum Period; D011247:Pregnancy; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D016216:Ultrasonography, Prenatal