Outcome of 1355 consecutive transabdominal chorionic villus samplings in 1351 patients

• Published in: Chinese medical journal Vol. 118; no. 20; pp. 1675 - 1681
• Main Author: LAU Tze Kin LEUNG Tak Yeung FUNG Tak Yuen CHAN Lin Wai Daljit S SAHOTA LEUNG Tse Ngong
• Format: Journal Article
• Language: English
• Published: Department of Obstetrics and Gynaecology Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, Hong Kong SAR, China 20-10-2005
• Subjects: 并发症; 腹部绒毛膜; 遗传疾病; chorionic villus sampling; postoperative complication; pregnancy outcome
• ISSN: 0366-6999; 2542-5641

Background The true risk of choronic villus sampling （CVS） is poorly defined. The objective of this study was to review the clinical outcome of transabdominal CVS performed in a university teaching unit, with an emphasis on the complication rate.
Methods A comprehensive audit database was maintained for 1351 pregnant women, including 17 sets ot twin pregnancies, who had a CVS. Details and outcome of all CVSs made in the unit between May 1996 and May 2004 were reviewed. All CVSs were performed by one of 5 operators using the identical techniques.
Results All procedures were performed transabdominally. A total of 1355 CVSs were performed because there were 4 dichorionic twin pregnancies which required 2 punctures. The mean gestation at CVS was （ 11.8 ＋ 0. 7 ） weeks, and 97.3% of the procedures were performed between 11 and 13 completed weeks. The majority （96. 2% ） required only 1 puncture to achieve correct needle placement. The procedure failed to obtain an adequate sample in 4 subjects （0.30%）. A total of 1351 chromosomal studies were requested and there was 1 case （0. 07% ） of culture failure. The results of chromosomal studies were available within 14 days in 36. 7% of the cases and within 21 days in 94. 0%. Overall, 77 chromosomal abnormalities （5.7%） and 5 cases of thalassemia major were detected. Pregnancy outcome was unknown in only 13 singleton subjects （0.96%）. In the remaining 1355 fetuses, there were 76 pregnancy terminations （5.56%）, 10 fetal losses with obvious obstetric causes （0. 73% ）, and 21 potentially procedure-related fetal losses （ 1.54% ）. In the last group, the majority had one or more co-existing obstetric complications. The background fetal loss rate for pregnancies at similar gestational age in the unit was about 0. 8%. Therefore, the procedure-related fetal loss rate was estimated to be at the maximum of 0. 74%.
Conclusions In experienced hands, first trimester transabdominal CVS is an accurate and safe invasive prenatal diagnostic procedure. It should be one of the treatment options available to pregnant women who require prenatal genetic diagnosis.