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Impact of Day 2 Versus Day 3 Fresh Embryo Transfer on Live Birth Rate in Poor-Prognosis Patients

Impact of Day 2 Versus Day 3 Fresh Embryo Transfer on Live Birth Rate in Poor-Prognosis POSEIDON Group 4 Patients: A Single-Center, Parallel-Group, Open-Label Randomized Controlled Trial

Status
Not yet recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07533695
Enrollment
470
Registered
2026-04-16
Start date
2026-03-30
Completion date
2027-12-31
Last updated
2026-04-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Female Infertility Due to Diminished Ovarian Reserve, Low Prognosis in Assisted Reproductive Technology, POSEIDON Category 4

Keywords

fresh embryo transfer, in-vitro fertilization, POSEIDON, low prognosis, diminished ovarian reserve

Brief summary

This study aimed to compare the efficacy (live birth rate) of fresh embryo transfer on Day 2 versus Day 3 in POSEIDON Group 4 patients, and to determine the optimal timing of embryo transfer for this population. It is a single-center, parallel-group, open-label prospective randomized controlled trial, and outcome assessors are masked. The main questions it aims to answer are: Is there a significant difference in the live birth rate between Day 2 and Day 3 fresh embryo transfer in patients with POSEIDON Category 4 low prognosis? What are the differences in secondary outcomes (including clinical pregnancy rate, ongoing pregnancy rate, implantation rate, embryo utilization rate, miscarriage rate, incidence of moderate/severe OHSS, and adverse neonatal outcomes) between the two embryo transfer timings, and which timing is safer and more effective for this patient population? A total of 470 patients meeting the POSEIDON Category 4 criteria will be enrolled and randomly assigned to the Day 2 Fresh Embryo Transfer Group and the Day 3 Fresh Embryo Transfer Group in a 1:1 ratio using stratified block randomization. Researchers will compare the two groups to clarify the difference in live birth rate (primary outcome) and other secondary outcomes, so as to determine the optimal embryo transfer timing. Participants will: * Be female patients aged ≥ 35 years with antral follicle count (AFC) \< 5 or anti-Müllerian hormone (AMH) \< 1.2 ng/mL, undergoing the first or second IVF/ICSI cycle, receiving controlled ovarian hyperstimulation (COH) with the GnRH antagonist protocol, and having ≥ 1 oocyte retrieved (excluding those using donor oocytes/sperm, with uterine cavity abnormalities, or complicated with severe underlying diseases). * Be randomly assigned to either the Day 2 Fresh Embryo Transfer Group or the Day 3 Fresh Embryo Transfer Group, and receive embryo transfer according to the corresponding group's protocol * Receive routine luteal support treatment after embryo transfer * Attend follow-up visits at multiple time points (on the day of transfer, 12-15 days after transfer, 28 days after transfer, during pregnancy, and after delivery) to collect relevant clinical and laboratory data for outcome assessment. * Undergo safety evaluation throughout the study; the study will adopt intention-to-treat (ITT) as the main statistical method and per-protocol (PP) as the sensitivity analysis, with subgroup analysis by age, AMH level, and number of oocytes retrieved, following ethical norms and data quality control requirements.

Interventions

PROCEDUREDay 2 Fresh Embryo Transfer

Embryos will be cultured for 44-48 hours after oocyte retrieval (Day 2), and embryos with ≥ 2 cells, grade II or above, and no multinucleation will be selected for transfer, with 1-2 embryos transferred; routine luteal support treatment will be given after transfer.

Sponsors

Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender
FEMALE
Age
35 Years to 50 Years
Healthy volunteers
No

Inclusion criteria

* 1: Meet the definition of POSEIDON Category 4: age ≥ 35 years, with antral follicle count (AFC) \< 5 or anti-Müllerian hormone (AMH) \< 1.2 ng/mL * 2: Undergoing first or second IVF/ICSI cycle * 3: Undergoing controlled ovarian hyperstimulation (COH) using a gonadotropin-releasing hormone (GnRH) antagonist protocol, with at least 1 oocyte retrieved * 4: Provide written informed consent

Exclusion criteria

* 1: Use of donor oocytes/sperm, or planned preimplantation genetic testing (PGT) * 2: Severe immune or chromosomal abnormalities * 3: Uterine cavity abnormalities (i.e., submucous fibroids, complete uterine septum, severe intrauterine adhesions, etc.) or untreated, ultrasound-visible hydrosalpinx * 4: Presence of severe underlying diseases (e.g., uncontrolled hypertension/diabetes mellitus, active malignant tumors) * 5: History of recurrent implantation failure (≥2 cycles) or recurrent miscarriage (≥2 episodes) * 6: Progesterone level \> 1.5 ng/mL on the day of human chorionic gonadotropin (hCG) trigger

Design outcomes

Primary

MeasureTime frameDescription
Live birth rateFrom enrollment to deliveryLive birth rate, defined as the delivery of at least one neonate with heartbeat and breathing at ≥ 28 weeks of gestation.

Secondary

MeasureTime frameDescription
Congenital malformation rateFrom enrollment to 1 month after deliveryThe proportion of participants who achieved a live birth and delivered a newborn diagnosed with a congenital malformation according to the International Classification of Diseases (ICD-10).
Low birth weight rateFrom enrollment to the deliveryThe proportion of participants who achieved a live birth and delivered a newborn with a birth weight of less than 2500g.
Embryo utilization rateDay 2 or Day 3 after oocyte retrievalThe proportion of all obtained fertilized embryos (2PN zygotes) that are available for subsequent embryo transfer.
Moderate/severe OHSS incidence rateFrom oocyte retrieval to 12 weeks of gestationThe proportion of participants enrolled in the study who developed moderate or severe ovarian hyperstimulation syndrome (OHSS), meeting the criteria of the Royal College of Obstetricians and Gynaecologists (RCOG), between oocyte retrieval and 12 weeks of gestation.
Miscarriage rateFrom enrollment to ≤28 weeks of gestationThe proportion of participants who experienced a clinical pregnancy and subsequently had a spontaneous pregnancy loss before 28 weeks of gestation.
Clinical pregnancy rateFrom enrollment to 28 days after embryo transferThe proportion of participants enrolled in the study who experienced a clinical pregnancy, defined as the confirmation of an intrauterine gestational sac via ultrasound examination 28 days after embryo transfer.
Implantation rateFrom enrollment to 28 days after embryo transferThe proportion of all transferred embryos that developed into an intrauterine gestational sac, as confirmed by ultrasound examination 28 days after embryo transfer.
Rate of no available embryosDay 2 or Day 3 after oocyte retrievalThe proportion of participants enrolled in the study who, following ovarian stimulation, oocyte retrieval, and embryo culture, have no embryos available for transfer.
Biochemical pregnancy rateFrom enrollment to 14 days (D3) or 15 days (D2) after embryo transferThe proportion of participants enrolled in the study who experienced a biochemical pregnancy, defined as a serum HCG level ≥25 IU/L measured 14 or 15 days after embryo transfer.
Preterm birth rateFrom enrollment to the deliveryThe proportion of participants who achieved a live birth and delivered between 28 and 36⁺⁶ weeks of gestation.
Ongoing pregnancy rateFrom enrollment to 12 weeks of gestationThe proportion of participants enrolled in the study who experienced an ongoing pregnancy, defined as the confirmation of an intrauterine viable fetus via ultrasound examination at 12 weeks of gestation.

Contacts

CONTACTSHUTIAN JIANG, Medical Doctor
shutiansweet@126.com021-23271699

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 17, 2026