Survey Of Embryo Transfer (E/T) Practice In UK And Abroad
Rajah SV, Tillisi A, Haloob R. Brentwood Fertility, Essex Nuffield Hospital, Brentwood, Essex CM15 8EH, UK19 April 2007
ET is the final step in IVF/ICSI treatment cycles. The entire assisted conception cycle depends on delicate placement of embryos at the proper location in the uterine cavity. Some studies claimed improvement in the pregnancy rate (PR) by minor adjustment to ET procedure such as type of catheter, time of withdrawal of catheter and recently cervical clamping of cervix to minimise the expulsion of embryos.
We devised a questionnaire to determine ET practice in UK and abroad. Total of 85 Assisted Conception Units in UK were sent a questionnaire. The same questionnaire was given to participants of 2005 ESHRE meeting in Denmark and was made available on IVF Net web site. (Questionnaire is on slide for presentation).
We had response from 45 units from UK and 39 from abroad.
Our survey showed the majority of units carried out 300 to 400 cycles per year (range 100 to 2500) in UK and abroad and a standard protocol is in place to carryout the procedure. The average PR for IVF/ICSI cycles world wide varies from 26 to 32% (range 20% to 55%). Trial ET increased the PR in UK and internationally (33%vs28%) & (42%vs36%). Ultrasound guided (US) ET was routinely done in 65% of UK units and 75% of international units. No difference found in PR in UK units but a significant increase observed in US/ET in international units (26%vs33%). Day 3 ET has improved the PR in both groups compared to day 2 ET. Day 5 ET is selectively used in UK units and the PR is greatly increased compared to day 3 or 2 ET (55%vs33%). Medication to relax the uterus is not widely used in UK and abroad. 1 unit in UK and 3 units abroad used voltral prior to ET. PR for both group are 50% and 38%. The type of ET catheter widely used in UK and abroad is Wallace and Cook and no difference in PR found. Majority of units in UK and abroad withdraw the catheter after 30 sec or 30 - 60 sec of ET. There is no difference in PR observed. Bed rest after ET is recommended in international units, not in UK units. Clamping of cervix is not in practice in both groups. Pre and Post ET medication such as Heparin and Aspirin has been used on selective patients (recurrent miscarriage, repeat failure) in UK units and seen significant increase in PR (26%vs35%).
This survey showed us the practice of ET procedure in UK and abroad is varies in different stages but the PR is not greatly affected. The pregnancy rate has improved with Day 5 ET in both groups. Trial ET and US/ET has an effect on PR and would be useful to practice routinely to all patients. Also US/ET can be reassuring to the patient the location of the embryo in the uterus. Using relaxant and anticoagulant prior and post ET seems to have an effect on pregnancy rate but need more study to confirm this.
Finally, I would like to thank all my UK colleagues and web members who participated in this survey. Please contact me if you need any more information on this survey.