Effect of Low Molecular Weight Heparin in Freeze-thaw Embryo Transfer Cycles in Women With Recurrent Implantation Failure

NCT06991530 | Completed

• 1 other identifier: KYLL2025342
• Study Type: observational
• Target: 392
• Locations: 1 country
• Sites: 1

Brief Summary

Recurrent implantation failure (RIF) is considered a tough problem in assisted reproductive technology (ART) without effective treatments. The effect of low molecular weight heparin (LMWH) in pregnancy outcomes is controversial. In addition, there are few reports on the role of LMWH in population with RIF performing freeze-thaw embryo transfer (FET) cycles. The purpose of this study is to evaluate the effect of LMWH on pregnancy outcomes in women with FET cycles.

Conditions

Low Molecular Weight Heparin; Recurrent Implantation Failure; FET; IVF

Outcome Measures

Primary Outcomes (1)

• Ongoing pregnancy rate

  The number of ongoing pregnancies divided by the number of women who received a transfer

  from transplantation to delivery (assessed up to 40 weeks of gestation)

Secondary Outcomes (4)

• biochemical pregnancy rate

  from transplantation to delivery (assessed up to 40 weeks of gestation)

• clinical pregnancy rate

  from transplantation to delivery (assessed up to 40 weeks of gestation)

• ectopic pregnancy rate

  from transplantation to delivery (assessed up to 40 weeks of gestation)

• Miscarriage rate

  from transplantation to delivery (assessed up to 40 weeks of gestation)

Study Arms (2)

LMWH group

the LMWH group received injections of 4100 IU/d LMWH from the day of transplant

Drug: Low Molecular Weight Heparine

Control group

the control group received the routine luteal support protocol (without LMWH use)

Interventions

Low Molecular Weight Heparine DRUG

the LMWH group received injections of 4100 IU/d LMWH from the day of transplant

LMWH group

Eligibility Criteria

• Age: 20 Years - 40 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study analyzed the data from the hospital electronic database for patients undergoing FET between January, 2021 and November, 2024, a total of 392 transplant cycles, who undergoing at least two IVF or ICSI cycles from the Second Hospital of Shandong University.

You may qualify if:

• Women under or equal to the age of 40 when oocytes were retrieved;
• The history of at least 2 failed fresh embryo transfer/FET cycles and cumulative transfer of ≥ 3 high-quality embryos or cumulative transfer of ≥ 2 blastocysts;
• Planning to FET after IVF or ICSI cycles

You may not qualify if:

• Women with untreated hydrosalpinx, uterine cavity occupying lesions (uterine adhesions, submucous fibroids, endometrial polyps, et al.);
• Women with abnormal anatomical structure of uterus (unicornuate uterus, bipedal uterus, et al.);
• Women with endometrial thickness (EMT) \< 6mm on the day of transplantation;
• Women or their partner with abnormal chromosome karyotype (not including chromosome polymorphisms);
• Women with the history of recurrent spontaneous abortion (RSA);
• Women with a history of autoimmune or coagulation disorders;
• Women with contraindications to LMWH

Sponsors & Collaborators

• The Second Hospital of Shandong University: lead

Study Sites (1)

The Second Hospital of Shandong University

Jinan, Shandong, China

Location

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: professor

Study Record Dates

• First Submitted: April 29, 2025
• First Posted: May 28, 2025
• Study Start: January 1, 2021
• Primary Completion: November 30, 2024
• Study Completion: March 1, 2025
• Last Updated: August 12, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)