Day-4 Embryo Defragmentation: Blastocyst Rate and clInical Outcomes

Recruiting now · Not applicable

Conditions studied: Female Infertility, Embryo Development, In Vitro Fertilization

In brief

Background: Embryo fragmentation is one of the main morphological parameters assessed during in vitro culture in assisted reproductive technology (ART). The presence of anucleate cytoplasmic fragments is commonly observed in human embryos and may negatively affect developmental potential and clinical outcomes. Embryo defragmentation at early stages (Day 2-3) is an established technique in some centers, but evidence remains heterogeneous. Defragmentation at Day 4 (morula/compaction stage) represents a significantly less explored area, with promising but insufficient data to guide clinical practice. Study Objective: This study aims to evaluate whether mechanical or laser-assisted embryo defragmentation performed on Day 4 (D4) of in vitro culture improves blastocyst development rates and clinical outcomes in ART cycles, compared to standard culture without intervention. Study Design: This is a prospective, randomized controlled trial (RCT) with single-blind assessment. Patients undergoing IVF/ICSI with embryos showing ≥10% fragmentation at D4 morphological evaluation will be randomly assigned (1:1 ratio) to one of two groups: Group A (Intervention): Mechanical/laser defragmentation at D4, followed by standard blastocyst culture Group B (Control): Standard blastocyst culture without any additional manipulation Randomization will be performed at the patient level using pre-generated block randomization lists, stratified by patient age (\<35 vs. ≥35 years), number of fragmented embryos at D4, and use of preimplantation genetic testing (PGT-A). Participants: Women aged 18-43 years undergoing IVF/ICSI cycles, with at least one embryo showing ≥10% fragmentation at D4 and destined for blastocyst culture. Key exclusion criteria include: donor gamete cycles, PGT-M as primary indication, embryos with \>50% fragmentation, or severe morphological compromise at Day 3. Primary Outcome: Rate of usable blastocysts (Gardner score ≥3BB) per embryo included in the study, assessed at Day 5 and Day 6 of culture. Secondary Outcomes: Overall blastocyst development rate (D5/D6), Gardner score distribution, blastocyst cryopreservation rate, implantation rate, clinical pregnancy rate (heartbeat at 7 weeks), ongoing pregnancy rate (beyond 12 weeks), live birth rate per transfer, and morphokinetic analysis (if time-lapse incubator available). Sample Size: Approximately 240 patients total (120 per arm), based on an expected blastocyst rate of \~42% in the control group vs. \~57% in the intervention group (15% absolute difference), with 80% power and α=0.05. A 15% dropout correction is applied. Duration: 6 months of enrollment plus 6 months of clinical follow-up (total \~12 months).

Key facts

Study ID: NCT07500337
Run by: Momo Fertilife
People needed: 320
Starts: 2026-03-24
Expected to finish: 2026-12-31
Last updated by the study team: 2026-03-30

Who can join

Age: 20 and older, up to 42. Sex: female. Healthy volunteers: not accepted.

You may qualify if…

Female patients undergoing ICSI cycles at the participating center
Age 18-42 years
Presence of at least one morula with cytoplasmic fragmentation ≥10% at Day 4 morphological assessment (Grade B: 10-25%, Grade C: 26-50%, Grade D: ≥50%)
Embryos intended for extended culture to blastocyst stage (Day 5/Day 6)
All embryo cultures performed in time-lapse incubator (Geri, Genea Biomedex)
Written informed consent obtained prior to any study-related procedure -

You may not qualify if…

Severely reduced ovarian reserve (AMH ≤ 0.5 ng/mL)
Body mass index (BMI) ≥ 32 kg/m²
Diagnosis of endometriosis
Polycystic ovary syndrome (PCOS)
Maternal age ≥ 42 years
History of repeated implantation failure
Donor gamete cycles (oocyte or sperm donation)
Cycles with preimplantation genetic testing for monogenic disease (PGT-M) as primary indication
Embryos with severe morphological compromise at Day 3
Concurrent participation in other interventional studies that could interfere with study outcomes
Inability to provide written informed consent

Where it is running

MOMO' Fertilife — Bisceglie, BT, Italy (enrolling)

Full record on ClinicalTrials.gov

Trial information comes from ClinicalTrials.gov and is refreshed daily. TrialsForMe does not provide medical care and does not run the studies it lists.