NCT07692672

Brief Summary

Thin endometrium is a condition in which the lining of the uterus is too thin during preparation for embryo transfer. This may reduce the chance of pregnancy and live birth in patients undergoing frozen-thawed embryo transfer. This study will evaluate whether intrauterine infusion of granulocyte colony-stimulating factor, also called G-CSF, can improve pregnancy outcomes in patients with thin endometrium. Participants will be randomly assigned to one of two groups. The experimental group will receive mild endometrial stimulation followed by intrauterine infusion of G-CSF 300 μg. The control group will receive the same mild endometrial stimulation followed by intrauterine infusion of normal saline. Both groups will then continue standard endometrial preparation for frozen-thawed embryo transfer. The main outcome of the study is the live birth rate. The study will also assess endometrial thickness, endometrial blood flow, clinical pregnancy rate, miscarriage rate, and safety outcomes, including adverse events, pregnancy complications, fetal malformations, and neonatal birth defects. Participants will be followed from enrollment through embryo transfer, pregnancy assessment, and delivery. This is a single-center, prospective, randomized controlled trial conducted at Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School. The planned sample size is 620 participants.

Trial Health

65
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Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
620

participants targeted

Target at P75+ for phase_3

Timeline
35mo left

Started Oct 2026

Typical duration for phase_3

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 4, 2026

Completed
5 days until next milestone

First Posted

Study publicly available on registry

July 9, 2026

Completed
3 months until next milestone

Study Start

First participant enrolled

October 1, 2026

Expected
2.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2029

Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2029

Last Updated

July 9, 2026

Status Verified

July 1, 2026

Enrollment Period

2.8 years

First QC Date

July 4, 2026

Last Update Submit

July 8, 2026

Conditions

Keywords

Thin EndometriumG-CSFIntrauterine InfusionFrozen-Thawed Embryo TransferLive Birth Rate

Outcome Measures

Primary Outcomes (1)

  • Live Birth Rate

    The proportion of participants who deliver at least one live-born infant after the registered frozen-thawed embryo transfer cycle. Live birth is defined as delivery of at least one newborn with signs of life at 28 weeks of gestation or later.

    From embryo transfer to delivery, approximately 40 weeks after embryo transfer

Secondary Outcomes (4)

  • Endometrial Thickness

    On the day 1 of endometrial transformation

  • Endometrial and Sub-endometrial Blood Flow

    On the day 1 of endometrial transformation

  • Clinical Pregnancy Rate

    4 to 6 weeks after embryo transfer

  • Early Miscarriage Rate

    From confirmation of clinical pregnancy to 12 weeks of gestation

Study Arms (2)

Mild Endometrial Stimulation With Intrauterine G-CSF Infusion

EXPERIMENTAL

Participants in this arm will undergo mild endometrial stimulation followed by intrauterine infusion of G-CSF 300 μg during the endometrial preparation cycle for frozen-thawed embryo transfer.

Biological: Granulocyte Colony-Stimulating Factor(G-CSF)

Mild Endometrial Stimulation With Intrauterine Normal Saline Infusion

PLACEBO COMPARATOR

Participants in this arm will undergo the same mild endometrial stimulation procedure followed by intrauterine infusion of an equal volume of normal saline during the endometrial preparation cycle for frozen-thawed embryo transfer.

Drug: Normal Saline

Interventions

Participants in the experimental arm will receive a single intrauterine infusion of G-CSF 300 μg after mild endometrial stimulation during the endometrial preparation cycle for frozen-thawed embryo transfer.

Also known as: Recombinant Human Granulocyte Colony-Stimulating Factor
Mild Endometrial Stimulation With Intrauterine G-CSF Infusion

Participants in the control arm will receive a single intrauterine infusion of an equal volume of normal saline after the same mild endometrial stimulation procedure during the endometrial preparation cycle for frozen-thawed embryo transfer.

Also known as: Saline
Mild Endometrial Stimulation With Intrauterine Normal Saline Infusion

Eligibility Criteria

Age18 Years - 39 Years
Sexfemale
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Female patients aged 18 to \<40 years.
  • Patients with normal ovarian function.
  • History of endometrial thickness ≤7 mm in at least one previous endometrial preparation cycle.
  • At least two good-quality embryos remaining.
  • Fewer than 3 previous embryo transfer cycles.
  • Willing and able to provide written informed consent.

You may not qualify if:

  • Uterine diseases or conditions that may affect the uterine cavity, including intramural uterine fibroids affecting the uterine cavity, severe adenomyosis, endometriosis, uterine malformation, endometrial tuberculosis, or severe untreated intrauterine adhesions.
  • Endometrial lesions, history of pelvic tumors, or previous radiotherapy or chemotherapy.
  • Known allergy to G-CSF.
  • Current participation in another clinical study.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Related Publications (3)

  • Lian R, Wang X, Lin R, Zeng H, Zeng Y, Liu S. Evaluation of granulocyte colony-stimulating factor on the treatment of thin endometrium during frozen-thawed embryo transfer cycles: a retrospective cohort study. Gynecol Endocrinol. 2020 Apr;36(4):370-374. doi: 10.1080/09513590.2019.1658187. Epub 2019 Aug 29.

  • Zhu YC, Sun YX, Shen XY, Jiang Y, Liu JY. Effect of intrauterine perfusion of granular leukocyte-colony stimulating factor on the outcome of frozen embryo transfer. World J Clin Cases. 2021 Oct 26;9(30):9038-9049. doi: 10.12998/wjcc.v9.i30.9038.

  • Liu KE, Hartman M, Hartman A. Management of thin endometrium in assisted reproduction: a clinical practice guideline from the Canadian Fertility and Andrology Society. Reprod Biomed Online. 2019 Jul;39(1):49-62. doi: 10.1016/j.rbmo.2019.02.013. Epub 2019 Mar 20.

MeSH Terms

Conditions

Infertility, Female

Interventions

Saline SolutionSodium Chloride

Condition Hierarchy (Ancestors)

Genital Diseases, FemaleFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesGenital DiseasesInfertility

Intervention Hierarchy (Ancestors)

Crystalloid SolutionsIsotonic SolutionsSolutionsPharmaceutical PreparationsChloridesHydrochloric AcidChlorine CompoundsInorganic ChemicalsSodium Compounds

Study Officials

  • Yue Jiang

    Nanjing Drum Tower Hospital: Nanjing University Medical School Affiliated Nanjing Drum Tower Hospital

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Study Design

Study Type
interventional
Phase
phase 3
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Masking Details
Participants, outcome assessors, and statistical analysts will be blinded to group assignment. The intrauterine procedure will be performed in the same manner in both groups, and participants will not be informed whether they receive G-CSF or normal saline. Outcome assessors will not participate in randomization or the intrauterine procedure, and ultrasound and clinical outcome data will be assessed using anonymized identifiers. Statistical analysts will receive coded group information as Group A and Group B. The physician performing the intrauterine procedure will not be blinded because they must prepare and administer the assigned infusion.
Purpose
TREATMENT
Intervention Model
PARALLEL
Model Details: Participants will be randomly assigned in a 1:1 ratio to either mild endometrial stimulation with intrauterine G-CSF infusion or mild endometrial stimulation with intrauterine normal saline infusion.
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Research Professor

Study Record Dates

First Submitted

July 4, 2026

First Posted

July 9, 2026

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

August 1, 2029

Study Completion (Estimated)

August 1, 2029

Last Updated

July 9, 2026

Record last verified: 2026-07

Data Sharing

IPD Sharing
Will not share

Individual participant data will not be shared because the study involves sensitive reproductive, pregnancy, delivery, and neonatal clinical information. The current study protocol and informed consent documents do not include a plan for public sharing of individual participant data. De-identified aggregate data may be reported in scientific publications.