TRANSFER OF EMBRYOS INTO THE UTERUS - HOW MUCH DO TECHNICAL FACTORS AFFECT PREGNANCY RATES

Objective: Our objective was to identify the effect on outcome of (a) ultrasound-assisted embryo transfer, (b) the use of different embryo t ransfer catheters, and (c) the length of time the patients remain in t he supine position after embryo transfer. Setting: The setting was a p rivate fertility center. Subjects: This was a prospective study of 178 in vitro fertilization and embryo transfers (IVF-ET) and 63 frozen em bryo replacements (FER). Results: The pregnancy rate was 28.7% followi ng IVF-ET and 31.8% for FER. Ultrasound-assisted transfer did not affe ct the outcome (29 vs 30.3%). There was no difference in the performan ce of the Wallace and Frydman catheters with regard to outcome (30.3 v s 30.7%). Although there was an increase in pregnancy rate as the time interval in the supine position after ET increased, this needs a larg er study. Conclusion: The parameter studies did not affect the outcome of IVF/ET or FER. Some factors encouraged us to recommend ultrasound- assisted transfer in some cases, and the use of a Frydman catheter for transfer and to encourage the supine position after transfer for long er periods.