Late first-trimester invasive prenatal diagnosis: Results of an international randomized trial Article

Philip, J, Silver, RK, Wilson, RD et al. (2004). Late first-trimester invasive prenatal diagnosis: Results of an international randomized trial . 103(6), 1164-1173. 10.1097/01.AOG.0000128049.73556.fb

cited authors

  • Philip, J; Silver, RK; Wilson, RD; Thom, EA; Zachary, JM; Mohide, P; Mahoney, MJ; Simpson, JL; Platt, LD; Pergament, E; Hershey, D; Filkins, K; Johnson, A; Shulman, LP; Bang, J; MacGregor, S; Smith, JR; Shaw, D; Wapner, RJ; Jackson, LG

fiu authors


  • OBJECTIVE: To assess, in a randomized trial, the safety and accuracy of amniocentesis and transabdominal chorionic villus sampling (CVS) performed at 11-14 weeks of gestation, given that this time frame is increasingly relevant to early trisomy screening. METHODS: We compared amnioceatesis with CVS from 77 to 104 days of gestation in a randomized trial in a predominantly advanced maternal age population. Before randomization, the feasibility of both procedures was confirmed by ultrasonography, and experienced operators performed sampling under ultrasound guidance; conventional cytogenetic analysis was employed. The primary outcome measure was a composite of fetal loss plus pre-term delivery before 28 weeks of gestation in cytogenetically normal pregnancies. RESULTS: We randomized 3,775 women into 2 groups (1,914 to CVS; 1,861 to amniocentesis), which were comparable at baseline. More than 99.6% had the assigned procedure, and 99.9% were followed through delivery. In contrast to previous thinking, in the cytogenetically normal cohort (n = 3,698), no difference in primary study outcome was observed: 2.1% (95% confidence interval 1.5, 2.8) for CVS and 2.3% (95% confidence interval, 1.7, 3.1) for amniocentesis. However, spontaneous losses before 20 weeks and procedure-related, indicated terminations combined were increased in the amniocentesis group (P = .07, relative risk 1.74). We found a 4-fold increase in the rate of talipes equinovarus after amniocentesis (P = .02) overall and in week 13 (P = .03, relative risk = 4.65), but data were insufficient to determine this risk in week 14. CONCLUSION: Amniocentesis at 13 weeks carries a significantly increased risk of talipes equinovarus compared with CVS and also suggests an increase in early, unintended pregnancy loss. © 2004 by The American College of Obstetricians and Gynecologists.

publication date

  • June 1, 2004

Digital Object Identifier (DOI)

start page

  • 1164

end page

  • 1173


  • 103


  • 6