Isolated clubfoot diagnosed prenatally: Is karyotyping indicated?

Objective: To evaluate the appropriateness of fetal karyotyping after prena tal sonographic diagnosis of isolated unilateral or bilateral clubfoot. Methods: We retrospectively reviewed a database of fetal abnormalities diag nosed by ultrasound at a single tertiary referral center from July 1994 to March 1999 for eases of unilateral or bilateral clubfoot. Fetuses who had a dditional anomalies diagnosed prenatally, after targeted sonographic fetal anatomy surveys, were excluded. Outcome results included fetal karyotype di agnosed by amniocentesis, or newborn physical examination by a pediatrician . Results: During the 5-year period, 5731 fetal abnormalities were diagnosed from more than 27,000 targeted prenatal ultrasound examinations. There were 51 cases of isolated clubfoot. The mean maternal age at diagnosis was 30.5 years. The mean gestational age at diagnosis was 21.6 weeks. Twenty-three of the women (45%) were at increased risk of fetal aneuploidy, on the basis of advanced maternal age or abnormal maternal serum screening. Six women ( 12%) had positive family histories of clubfoot; however, no cases of aneupl oidy were found by fetal karyotype evaluation or newborn physical examinati on. All cases of clubfoot diagnosed prenatally were confirmed at newborn ph ysical examination, and no additional malformations were detected. Conclusion: After prenatal diagnosis of isolated unilateral or bilateral cl ubfoot, there appeared to be no indication to offer karyotyping, provided t hat a detailed sonographic fetal anatomy survey was normal and there were n o additional indications for invasive prenatal diagnoses. (Obstet Gynecol 2 000;95:437-40. (C) 2000 by The American College of Obstetricians and Gyneco logists.).