Correspondence
757
Re: Ultrasound guidance during embryo transfer: a systematic review and meta-analysis of randomized controlled trials We read with interest the article of Teixeira et al.1 published in the February 2015 issue and commend their work. In 2006, we published a meta-analysis of the randomized studies then available, comparing ultrasound-guided embryo transfer to the ‘clinical-touch’ method and found that the live-birth rate was significantly higher when ultrasound guidance was used2 . In the same issue of the same Journal, Buckett published a similar meta-analysis and reached the same conclusions3 . Subsequently, a Cochrane review was published by Brown et al. in 2007 which found that the live-birth rate was indeed significantly higher when using ultrasound-guided embryo transfer compared to the clinical-touch method4 . These findings were accepted by the assisted reproduction community and more workers in the field started to perform their embryo transfers under ultrasound guidance5,6 . However, in 2008, Drakeley et al.7 published their large randomized study on 2295 patients and found that the live-birth rate was not significantly higher in the ultrasound-guided embryo transfer group. In their conclusion, the authors stated that their findings were
Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
Ultrasound Obstet Gynecol 2015; 45: 755–758.
Correspondence
758
‘at odds with the UK’s National Institute of Clinical Excellence recommendations for fertility treatment’. They also asked that the Cochrane review be updated with this new information and, hastily, this was subsequently done by Brown et al. in 2010; by including the Drakeley study, they found that the live-birth rate was not significantly higher in the ultrasound-guided group8 . Unfortunately, on careful reading of the Drakeley study, it emerges that a different embryo transfer catheter was used in each arm of the ‘randomized’ study: a ‘Cook Echotip Soft Pass’ catheter was used in the ultrasound-guided embryo-transfer group, while a ‘soft, non-echogenic Wallace’ or a ‘Rocket’ embryo-transfer catheter was used in the clinical-touch group (i.e. three different catheters were used in the two arms of the study). This, of course, violates the rules of randomization and it is questionable whether the study should have been included in the Cochrane meta-analysis at all. Unfortunately, letters to the editors of the Cochrane Library cannot be published. In his ‘Referee Commentary’ on the Teixeira paper, Dr Drakeley states that ultrasound-guided embryo transfer is beneficial because the clinician can confirm the site of embryo deposition9 . However, in our experience, published elsewhere10 , the main advantage of ultrasound guidance of embryo transfer is in facilitating the passage of the embryo-transfer catheter through the uterocervical angle, which is the main site of difficulty during the procedure. This is performed by bending the tip of the catheter according to this angle. Consequently, the current meta-analysis puts matters in their proper context and concludes, once again, that, when using the same catheter, ultrasound-guided
Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
embryo transfer is associated with a higher live-birth rate compared with the clinical-touch method. H. N. Sallam Obstetrics and Gynaecology, The University of Alexandria, Alexandria, Egypt; Alexandria Fertility Center, 22 Victor Emanuel Square, Smouha, Alexandria, Egypt 21615 (e-mail: [email protected]) DOI: 10.1002/uog.14859
References ˜ LA, Vieira CV, Barbosa MA, Coelho Neto MA, Nastri 1. Teixeira DM, Dassunc¸ao CO, Martins WP. Ultrasound guidance during embryo transfer: a systematic review and meta-analysis of randomized controlled trials. Ultrasound Obstet Gynecol 2015; 45: 139–148. 2. Sallam HN, Sadek SS. Ultrasound-guided embryo transfer: a meta-analysis of randomized controlled trials. Fertil Steril 2003; 80: 1042–1046. 3. Buckett WM. A meta-analysis of ultrasound-guided versus clinical touch embryo transfer. Fertil Steril 2003; 80: 1037–1041. 4. Brown JA, Buckingham K, Abou-Setta A, Buckett W. Ultrasound versus ‘clinical touch’ for catheter guidance during embryo transfer in women. Cochrane Database Syst Rev 2007 Jan 24; (1): CD006107. 5. Sallam HN. Embryo transfer: factors involved in optimizing the success. Curr Opin Obstet Gynecol 2005; 17: 289–298. 6. Sallam HN. Should embryo transfer always be performed under ultrasound guidance? Ultrasound Obstet Gynecol 2004; 24: 383–386. 7. Drakeley AJ, Jorgensen A, Sklavounos J, Aust T, Gazvani R, Williamson P, Kingsland CR. A randomized controlled clinical trial of 2295 ultrasound-guided embryo transfers. Hum Reprod 2008; 23: 1101–1106. 8. Brown J, Buckingham K, Abou-Setta AM, Buckett W. Ultrasound versus ‘clinical touch’ for catheter guidance during embryo transfer in women. Cochrane Database Syst Rev 2010 Jan 20; (1): CD006107. 9. Drakeley A. Re: Ultrasound guidance during embryo transfer: a systematic review ˜ and meta-analysis of randomized controlled trials. D. M. Teixeira, L. A. Dassunc¸ao, C. V. R. Vieira, M. A. P. Barbosa, M. A. Coelho Neto, C. O. Nastri and W. P. Martins. Ultrasound Obstet Gynecol 2015; 45: 139–148. Ultrasound Obstet Gynecol 2015; 45: 131. 10. Sallam HN, Agameya AF, Rahman AF, Ezzeldin F, Sallam AN. Ultrasound measurement of the uterocervical angle before embryo transfer: a prospective controlled study. Hum Reprod 2002; 17: 1767–1772.
Ultrasound Obstet Gynecol 2015; 45: 755–758.
757
Re: Ultrasound guidance during embryo transfer: a systematic review and meta-analysis of randomized controlled trials We read with interest the article of Teixeira et al.1 published in the February 2015 issue and commend their work. In 2006, we published a meta-analysis of the randomized studies then available, comparing ultrasound-guided embryo transfer to the ‘clinical-touch’ method and found that the live-birth rate was significantly higher when ultrasound guidance was used2 . In the same issue of the same Journal, Buckett published a similar meta-analysis and reached the same conclusions3 . Subsequently, a Cochrane review was published by Brown et al. in 2007 which found that the live-birth rate was indeed significantly higher when using ultrasound-guided embryo transfer compared to the clinical-touch method4 . These findings were accepted by the assisted reproduction community and more workers in the field started to perform their embryo transfers under ultrasound guidance5,6 . However, in 2008, Drakeley et al.7 published their large randomized study on 2295 patients and found that the live-birth rate was not significantly higher in the ultrasound-guided embryo transfer group. In their conclusion, the authors stated that their findings were
Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
Ultrasound Obstet Gynecol 2015; 45: 755–758.
Correspondence
758
‘at odds with the UK’s National Institute of Clinical Excellence recommendations for fertility treatment’. They also asked that the Cochrane review be updated with this new information and, hastily, this was subsequently done by Brown et al. in 2010; by including the Drakeley study, they found that the live-birth rate was not significantly higher in the ultrasound-guided group8 . Unfortunately, on careful reading of the Drakeley study, it emerges that a different embryo transfer catheter was used in each arm of the ‘randomized’ study: a ‘Cook Echotip Soft Pass’ catheter was used in the ultrasound-guided embryo-transfer group, while a ‘soft, non-echogenic Wallace’ or a ‘Rocket’ embryo-transfer catheter was used in the clinical-touch group (i.e. three different catheters were used in the two arms of the study). This, of course, violates the rules of randomization and it is questionable whether the study should have been included in the Cochrane meta-analysis at all. Unfortunately, letters to the editors of the Cochrane Library cannot be published. In his ‘Referee Commentary’ on the Teixeira paper, Dr Drakeley states that ultrasound-guided embryo transfer is beneficial because the clinician can confirm the site of embryo deposition9 . However, in our experience, published elsewhere10 , the main advantage of ultrasound guidance of embryo transfer is in facilitating the passage of the embryo-transfer catheter through the uterocervical angle, which is the main site of difficulty during the procedure. This is performed by bending the tip of the catheter according to this angle. Consequently, the current meta-analysis puts matters in their proper context and concludes, once again, that, when using the same catheter, ultrasound-guided
Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
embryo transfer is associated with a higher live-birth rate compared with the clinical-touch method. H. N. Sallam Obstetrics and Gynaecology, The University of Alexandria, Alexandria, Egypt; Alexandria Fertility Center, 22 Victor Emanuel Square, Smouha, Alexandria, Egypt 21615 (e-mail: [email protected]) DOI: 10.1002/uog.14859
References ˜ LA, Vieira CV, Barbosa MA, Coelho Neto MA, Nastri 1. Teixeira DM, Dassunc¸ao CO, Martins WP. Ultrasound guidance during embryo transfer: a systematic review and meta-analysis of randomized controlled trials. Ultrasound Obstet Gynecol 2015; 45: 139–148. 2. Sallam HN, Sadek SS. Ultrasound-guided embryo transfer: a meta-analysis of randomized controlled trials. Fertil Steril 2003; 80: 1042–1046. 3. Buckett WM. A meta-analysis of ultrasound-guided versus clinical touch embryo transfer. Fertil Steril 2003; 80: 1037–1041. 4. Brown JA, Buckingham K, Abou-Setta A, Buckett W. Ultrasound versus ‘clinical touch’ for catheter guidance during embryo transfer in women. Cochrane Database Syst Rev 2007 Jan 24; (1): CD006107. 5. Sallam HN. Embryo transfer: factors involved in optimizing the success. Curr Opin Obstet Gynecol 2005; 17: 289–298. 6. Sallam HN. Should embryo transfer always be performed under ultrasound guidance? Ultrasound Obstet Gynecol 2004; 24: 383–386. 7. Drakeley AJ, Jorgensen A, Sklavounos J, Aust T, Gazvani R, Williamson P, Kingsland CR. A randomized controlled clinical trial of 2295 ultrasound-guided embryo transfers. Hum Reprod 2008; 23: 1101–1106. 8. Brown J, Buckingham K, Abou-Setta AM, Buckett W. Ultrasound versus ‘clinical touch’ for catheter guidance during embryo transfer in women. Cochrane Database Syst Rev 2010 Jan 20; (1): CD006107. 9. Drakeley A. Re: Ultrasound guidance during embryo transfer: a systematic review ˜ and meta-analysis of randomized controlled trials. D. M. Teixeira, L. A. Dassunc¸ao, C. V. R. Vieira, M. A. P. Barbosa, M. A. Coelho Neto, C. O. Nastri and W. P. Martins. Ultrasound Obstet Gynecol 2015; 45: 139–148. Ultrasound Obstet Gynecol 2015; 45: 131. 10. Sallam HN, Agameya AF, Rahman AF, Ezzeldin F, Sallam AN. Ultrasound measurement of the uterocervical angle before embryo transfer: a prospective controlled study. Hum Reprod 2002; 17: 1767–1772.
Ultrasound Obstet Gynecol 2015; 45: 755–758.
