Effect of Intrauterine Insemination on Subsequent Pregnancy Outcomes in Couples With Unexplained Pregnancy Loss: A Multicenter, Open-label, Randomized Controlled Trial

August 6, 2026 updated by: Fang Wang, Lanzhou University Second Hospital

Unexplained pregnancy loss remains a major reproductive challenge, and effective management strategies for affected couples are limited. Although intrauterine insemination (IUI) is widely used in reproductive medicine, its effectiveness in improving subsequent pregnancy outcomes among couples with unexplained pregnancy loss has not been well established.

This multicenter, open-label, randomized controlled trial aims to evaluate whether IUI improves subsequent pregnancy outcomes compared with natural conception in couples with unexplained pregnancy loss. A total of 558 eligible couples will be enrolled and randomly assigned to either an IUI group or a natural conception group. Participants will be followed to assess reproductive outcomes. The findings of this study are expected to provide high-quality evidence regarding the role of IUI in the management of unexplained pregnancy loss and to inform future clinical practice.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

558

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • China
    • Beijing Municipality
      • Beijing, Beijing Municipality, China
        • Not yet recruiting
        • Beijing Amcare Beisanhuan Women's & Children's Hospital
        • Contact:
    • Gansu
      • Lanzhou, Gansu, China
        • Recruiting
        • Lanzhou university second hosipital
        • Contact:
    • Hebei
      • Shijiazhuang, Hebei, China
        • Not yet recruiting
        • Hebei Reproductive Health Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Female participants aged 20-37 years.
  • History of at least one ultrasound-confirmed pregnancy loss (excluding biochemical pregnancy, ectopic pregnancy, and hydatidiform mole), with the most recent pregnancy loss occurring within the previous 12 months.
  • Desire for pregnancy at the time of enrollment.
  • Basal follicle-stimulating hormone (FSH) <10 IU/L.
  • Anti-Müllerian hormone (AMH) >1.1 ng/mL.
  • Male partner's semen analysis meeting the criteria for intrauterine insemination (IUI), with a post-processing total progressive motile sperm count ≥5 × 10⁶.
  • Ability and willingness to provide written informed consent.

Exclusion Criteria:

  • Congenital or acquired uterine structural abnormalities.
  • Thyroid dysfunction, defined as thyroid-stimulating hormone (TSH) >4.0 mIU/L.
  • Positive antiphospholipid antibodies, including lupus anticoagulant, anticardiolipin antibodies, or anti-β2 glycoprotein I antibodies.
  • Parental chromosomal abnormalities or a history of fetal chromosomal abnormalities in a previous pregnancy.
  • Participation in another interventional clinical trial during the study period.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
No Intervention: Natural Conception
Participants attempt natural conception without intrauterine insemination.
Experimental: Intrauterine Insemination (IUI)
Participants undergo intrauterine insemination after randomization to improve the probability of conception.
Procedure: Intrauterine Insemination (IUI)
Participants assigned to the intervention group undergo intrauterine insemination (IUI) according to the study protocol. Processed sperm is placed into the uterine cavity during the periovulatory period to improve the likelihood of conception.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Early Miscarriage Rate
Time Frame: From randomization until 10 weeks of gestation
The proportion of women who experience pregnancy loss before 10 weeks of gestation among those achieving pregnancy.
From randomization until 10 weeks of gestation

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinical Pregnancy Rate
Time Frame: From randomization until clinical pregnancy assessment (6-8 weeks of gestation)
Clinical pregnancy confirmed by ultrasonographic visualization of an intrauterine gestational sac.
From randomization until clinical pregnancy assessment (6-8 weeks of gestation)
Live Birth Rate
Time Frame: From randomization until delivery (approximately 40 weeks of gestation)
Delivery of a live infant after 24 weeks of gestation.
From randomization until delivery (approximately 40 weeks of gestation)
Preterm Birth Rate
Time Frame: From randomization until delivery (approximately 40 weeks of gestation)
Delivery occurring between 28 and 37 completed weeks of gestation.
From randomization until delivery (approximately 40 weeks of gestation)
Adverse Event Rate
Time Frame: From enrollment until completion of study follow-up (approximately 40 weeks of gestation)
Occurrence of adverse events including ovarian hyperstimulation syndrome, infection, and other treatment-related complications.
From enrollment until completion of study follow-up (approximately 40 weeks of gestation)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Lanzhou University Second Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 27, 2026

Primary Completion (Estimated)

December 1, 2027

Study Completion (Estimated)

December 31, 2027

Study Registration Dates

First Submitted

July 23, 2026

First Submitted That Met QC Criteria

August 6, 2026

First Posted (Actual)

August 12, 2026

Study Record Updates

Last Update Posted (Actual)

August 12, 2026

Last Update Submitted That Met QC Criteria

August 6, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • 2025A-1361

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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