Received November 26, 2005
Accepted November 29, 2005

The effect of the ultrasound use during the embryo transfer (ET) on the pregnancy rates was evaluated by analyzing retrospectively 600 consecutive ICSI cycles. In the period between 01/01/1998 and 01/31/2000, 271 cycles were performed where ET was aided by ultrasound (Group A) which was compared to 329 cycles where ET was carried out without ultrasound (Group B). There were no statistically significant differences present in different variables such as cause of infertility, age of woman, fertilization rate and number of embryos transfered between the two groups. However, the implantation and clinicai pregnancy rates were significantly higher in the group where ET was performed with the aid of ultrasound (18,5% and 45% respectively) when compared to the group where the ultrasound was not used for ET (10,2% e 27,4% respectively, p<0,0001). In conclusion, the use of ultrasound for embryo transfer is recommended because it improves significantly the pregnancy rate in IVF-ET cycles.