Abstract A randomized clinical trial concerning immediate postplacental insertion (IPPI) of the Delta Lippes Loop, Delta TCu220C, and TCu220C was undertaken to assess the effect of the addition of catgut strands on IUD performance. A total of 906 devices were inserted and the subjects followed for 20 months, at which time 14,136 woman-months experience had been accumulated. The Delta Loop constantly had inadmissibly high expulsion and pregnancy rates. The two T-IUD models had significantly lower rates of expulsion and pregnancy, and these rates were similar for the sutured and the non-sutured TCu220C. Immediate postplacental insertion of the three IUD models was totally safe in terms of infection and perforation. Due to the difficulty of insertion and high expellability, the Delta Loop is considered unfit for IPPI. Performance of the TCu220C was good but the results did not indicate that “suturing” improved the retainability of this IUD model significantly.