Noninvasive Implantation Potential vs Morphology-Based Selection in IVF Single Blastocyst Transfer

Inclusion Criteria

• •1. Conventional IVF insemination;
• •2. Meeting either of the following:
• •1. Advanced maternal age: female age 35-43 years;
• •2. Recurrent miscarriage: ≥2 spontaneous pregnancy losses (\<28 gestational weeks), including biochemical pregnancy (hCG \>25 IU/L) ;
• •3. Willingness to culture all Day 3 embryos to the blastocyst stage in the fresh cycle, or to culture ≥6 embryos (with at least one embryo ≥7 cells), and to cryopreserve all blastocysts as single-blastocyst vitrification;
• •4. Willingness to undergo frozen-thawed single-blastocyst transfer;
• •5. At least two blastocysts formed on Day 5/Day 6 from 2PN fertilization, with morphological grading ≥4BC/4CB;
• •6. Provision of written informed consent.