This study aims to test the extent of association of FLIM parameters of cumulus cells with clinical outcomes (clinical pregnancy, ongoing pregnancy at 12 weeks, and live birth) of the embryos that result from the enclosed oocytes.

This study aims to test the extent of association of FLIM parameters of cumulus cells with clinical outcomes (clinical pregnancy, ongoing pregnancy at 12 weeks, and live birth) of the embryos that result from the enclosed oocytes.

Participants will be consented to and pre-signed following standard regimens of IVFMD, My Duc Hospital and IVFMD PN, My Duc Phu Nhuan Hospital. The standard is for patients with at least 8 follicles ≥ 10 mm on ultrasonography at the induced ovulation date.

Cumulus samples (CCs) will be collected following the protocol on the day of oocyte pick up (OPU), being assigned with the same number as the oocyte from which it was collected, and vitrified with a Cryotech kit until FLIM measurements are performed.

Insemination will be performed by using ICSI, 3 - 4 hours after oocyte retrieval. A sample of CCs will be sliced off the cumulus mass of each oocyte judged to be mature based on the cumulus mass disposition (absence of tight corona layers). The remaining cumulus cells will be stripped from the OCCs using hyaluronidase. Only mature oocytes will be inseminated.

The fertilization check will be performed under an inverted microscope for a period of 16-18 hours after insemination. On day 3, embryo evaluation will be performed at a fixed time point 66±2 hours after fertilization and, for day 5/6 transfers at 116±2 hours or 140±2 hours, respectively, using the Istanbul consensus. Freeze-all strategy for day 5 embryo will be applied and the first frozen embryo transfer cycle is single embryo transfer.

On the other hand, the investigators will stratify embryos into two groups based on the measured FLIM parameters from their associated cumulus cells, corresponding to the "high" 35% and "low" 65% of metabolic scores.

The investigators aim for embryos in the "high" metabolic scoring group to have a 10% higher live birth rate than controls. Assuming a current live birth rate of 32%, this corresponds to a hoped-for 42% live birth rate in the "high" group (and a 25% live birth rate in the "low" group). A total of 450 patients are required to detect an effect of this size (power 0.90, two-sided alpha 5%).

The primary endpoint of the study will be the live birth rate after the first embryo transfer of the started treatment cycle.

Inclusion Criteria:

• Having any number of IVF/ICSI attempts
• Ovarian stimulation with any stimulation protocol
• Patients with at least 8 follicles ≥ 10 mm on ultrasonography at induced ovulation date
• Agreed to freeze-all day 5-6 embryos
• Agreed to have a single day 5-6 embryo transfer.
• Agreed to participate in the research (signed the consent form)

Exclusion Criteria:

• In vitro maturation (IVM) cycles
• Cycles using testicular biopsy or epididymal sperm
• Cycles not having an oocyte freeze-all cycle
• Cycles using standard insemination
• Participating in another research

All Vietnamese infertile women who have IVF/ICSI cycle with at least 8 follicles ≥ 10 mm on ultrasonography at induced ovulation date agreed to freeze-all day 5-6 embryos at IVFMD and IVFMD PN will be enrolled in the study.