Cleavage-stage Versus Blastocyst-stage Embryo Transfer in IVF Patients With Few Embryos

Infertility affects more than 6 million women the United States and is a major life event that results in a wide range of socio-cultural, emotional, physical and financial problems. The most successful treatment for infertility, in-vitro fertilization (IVF), fertilizes a woman's eggs with her partner's sperm in a culture dish and transfers the resulting embryos into the uterus. Most of the time, prior to being transferred, embryos are grown in the dish for 5-7 days after which some of them reach an advanced stage (blastocyst stage). This has several advantages such as a lower chance of a multiple pregnancies (twins, triplets etc.) after transfer and fewer transfer procedures. However, it is possible that embryos would survive better if transferred into the uterus at the 8-cell stage after growing them for only 3 days. Thus, when patients only have a small number of embryos they and their physicians face the difficult choice when to transfer because there are currently no studies available to guide this decision. This randomized controlled trial is comparing pregnancy outcomes and patient satisfaction of poor prognosis patients with 5 or fewer embryos undergoing either transfer of an advanced (blastocyst) or an 8-cell embryo. This study will provide the data for the development of guidelines for IVF providers to make evidence-based decisions when to transfer embryos in poor prognosis IVF patients, reduce patients' anxiety regarding cycle cancellation and improve patient counseling, which will increase patients' ability to participate in the development of their treatment plan.

NCT Number	NCT06746129
Lead Sponsor	Beth Israel Deaconess Medical Center Collaborators: Brigham and Women's Hospital, Boston IVF, Columbia University, Weill Medical College of Cornell University, Mayo Clinic, University of Michigan, Patient-Centered Outcomes Research Institute, Massachusetts General Hospital (MGH), Yale University, UCSF Center for Reproductive Health, University of Pennsylvania
Conditions	Infertility (IVF Patients)
Enrollment	1,126 participants
Start Date	2025-09-10
Primary Completion	2030-12 (estimated)
Study Completion	2031-06-30 (estimated)
Updated on ClinicalTrials.gov	2026-04-02