Pregnancy Rates Stay High With Single Embryo Transfer

Since the development of fertility treatment, the risk of multiple births has been associated with IVF in the public mind. The transfer of multiple embryos increases pregnancy success, but also increases the chance for multiple births. However, techniques and technology have greatly improved in recent years and the total number of embryos per transfer can often be reduced to one single embryo.

Two recently published studies (Fertility & Sterility, Dec. 2005) conducted in Seattle and Australia show that implantation and birth rates are nearly the same when
patients transfer only one high quality embryo instead of two. In this study, patients with similar characteristics and diagnosis were divided into two groups, one group received a single embryo at the transfer and the second group received two embryos at the transfer. Results showed that there was a significant difference in the number of twins, while the pregnancy rate was nearly the same.

Dr. Kettel applauds the study results, but notes that the final decision on embryo numbers will depend on the patient’s diagnosis and medical history. A single embryo transfer is not for everyone.