Researchers in a 2026 study found that more than two-thirds of patients with complete embryo arrest still developed at least one usable blastocyst in their next IVF cycle, although they had lower usable blastocyst formation rates overall and were more likely to experience complete embryo arrest again.
A 2025 study introduces the term “oocyte and early embryo competence defects” to describe younger IVF patients who repeatedly have no transferable embryos due to low quality eggs, finding that about 13–23% had genetic changes.
A 2025 study of women with repeated IVF failure and unexplained infertility found that about 13% had mutations affecting egg or embryo development, mostly in the TUBB8 and PATL2 genes, suggesting that many “unexplained” cases may have underlying genetic causes.
Researchers in a 2024 study showed that by artificially removing the embryo’s zona (shell) right after fertilization reduced fragmentation, improved blastocyst development, and led to live births in patients with repeated IVF failure, though the findings are still preliminary and need confirmation in larger trials.
A 2024 study compared outcomes of IVF cycles that transferred day 2/3 or day 5/6 embryos, finding that day 2/3 embryos have higher live birth rates per cycle, particularly for patients with 3 or less embryos.
Researchers in a 2024 study found that patients that have 5 consecutive euploid transfers had a cumulative live birth rate of 98.1%, suggesting that most cases of implantation failure are due to the embryo, and that true unexplained RIF occurs in less than 2% of patients.
Researchers in a 2023 study discovered 6 genes associated with recurrent miscarriage of euploid embryos, which were found to impair reproductive ability in mouse models.
