The pregnancy rate for patients undergoing in-vitro fertilization (IVF) is improved when doctors use advanced 3D/4D imaging to guide the placement of embryos to the point where the endometrium is most receptive to implantation, according to a study presented today at the 63rd annual meeting of the American Society for Reproductive Medicine.
The study, “Maximal Implantation Potential (MIP) Point -- Suggested Target for Optimal Embryo Placement Within the Uterine Cavity During Embryo Transfer,” was led by Robert Gergely, MD.
Gergely has identified a new embryo placement target as the point where the fallopian tubes would intersect if they were extended beyond their natural length. The new target, or MIP point, is where embryos typically implant and develop in natural pregnancies.
The six-year retrospective, observational study, conducted at the 3D Sonography Center of Beverly Hills, evaluated 5,073 patients with a mean age of 38.3 years who received IVF using 3D/4D-guided embryo transfer. In each case, embryo placement was targeted at the MIP point.
The patients participating in the study achieved an overall pregnancy rate of 40.34 percent, which is 10.04 percent higher than the rate achieved prior to the introduction of the 3D/4D-guided MIP point technique in 2001. Earlier study results based on 1,222 patients were published in the August 2005 issue of the journal, Fertility and Sterility.
Using 3D ultrasound to locate the patient's MIP point, Gergely then guided the catheter tip using 4D imaging to the target location for the embryo transfer. Once the tip of the catheter was over the MIP point, the embryo was released and a distinct flash on the 4D image indicates the location of the embryo.
A total of 21 physicians have employed Gergely's technique. Once introduced, the MIP point was accepted over time as the optimal target for embryo placement by all of the physicians, and the 3D/4D-guided embryo transfer technique has been adopted as the standard operating procedure for all embryo transfers.
“The old technique for placing embryos using 2D ultrasound alone was essentially a guessing game,” said Gergely. “While 3D imaging allows doctors to visualize the entire uterine cavity and identify the MIP point, it's only with the addition of 4D imaging that we can target and guide embryos to the optimal, most natural location for each patient.”
The MIP point varies from patient to patient depending on the shape of the uterus and Gergely cautioned that even with the new technique, there remains significant room to improve the IVF pregnancy rate, which can be affected by several factors including the quality of embryos and receptivity of the endometrium.