INVESTIGATİON OF THE EFFECT OF PASSIVE UTERINE STRAIGHTENING WITH A FULL BLADDER IN COMBINATION WITH TRANSABDOMINAL ULTRASONOGRAPHY ON PREGNANCY RATES IN INTRAUTERINE INSEMINATION: A PROSPECTIVE COHORT STUDY

June 24, 2026 updated by: Mustafa YILMAZ, Firat University
In this prospective study, we aimed to compare the pregnancy outcomes of a classic blind IUI procedure with an empty bladder with a transabdominal ultrasound-guided IUI procedure where the cervicouterine angle was flattened by using a full bladder.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Intrauterine artificial insemination (IUI) is a procedure in which prepared sperm is placed into the uterine cavity via a catheter to help couples undergoing treatment for unexplained infertility to conceive. Many factors influence the success of IUI. In this prospective study, we aimed to compare the pregnancy outcomes of a classic blind IUI procedure with an empty bladder with a transabdominal ultrasound-guided IUI procedure where the cervicouterine angle was flattened by using a full bladder. This prospective study was conducted at the Firat University Infertility Clinic between 2021 and November 2022. The study included a total of 340 cases diagnosed with unexplained infertility who underwent gonadotropin induction and completed the study. Group 1 (n=169) = Group that underwent blind IUI with an empty bladder, Group 2 (n=171) = Group that underwent IUI with a full bladder under transabdominal ultrasound guidance. Demographic, laboratory, radiological, ovulation induction procedure, and pregnancy outcomes were compared between the two groups. When comparing the two groups, there were no significant differences in age, body mass index (BMI), basal hormone levels, total antral and dominant follicle count, total motile sperm count, and total gonadotropin dose. The amount of insemination fluid that overflowed from the uterine cavity was significantly greater in the full bladder group than in the empty bladder group. However, clinical pregnancy rates were similar in both groups. Performing the intrauterine insemination procedure with a full bladder under transabdominal ultrasound guidance does not positively affect clinical pregnancy rates, except in terms of ease of procedure.

Study Type

Observational

Enrollment (Actual)

340

Contacts and Locations

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

Study Locations

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

N/A

Sampling Method

Non-Probability Sample

Study Population

This prospective, randomised, single-centre study was conducted at the Fırat University Department of Obstetrics and Gynaecology, infertility clinic in Elazığ, Turkey, between 01/06/2021 and 03/11/2022.

Description

Inclusion criteria:

  1. The woman is aged between 18 and 39 inclusive.
  2. Cases with infertility lasting at least 12 months
  3. The presence of known medical indications for IUI.
  4. Cases with mild to moderate male factor infertility (cases with a total motile sperm count greater than 5 x 10⁶).
  5. Cases with ovulatory disorders
  6. Cases diagnosed with unexplained infertility
  7. Mixed infertility due to the known causes listed above.
  8. Patients who have started primary infertility treatment and those who have started secondary infertility treatment.
  9. Cases where ovarian stimulation was performed with gonadotropins.
  10. The ability to communicate with the couple verbally or in writing.

Exclusion criteria:

  1. Cases where unilateral or bilateral tubal passage is absent
  2. Cases with acute pelvic inflammatory disease
  3. Male partners who have fewer than 1 million motile sperm in semen analysis
  4. Endometriosis.

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

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Empty bladder
In the full bladder group, patients were asked to fill their bladders by drinking water until they felt the need to urinate, thus passively flattening the uterus. Uterine flattening was determined by transabdominal ultrasonography when the angle was ≥120°.
Other: filling bladder
filling and emptying the bladder
Full bladder
Patients undergoing blind IUI with an empty bladder were asked to empty their bladders by urinating prior to the procedure.
Other: filling bladder
filling and emptying the bladder

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinical Pregnancy
Time Frame: two weeks after IUI

Women were instructed to perform a blood pregnancy test two weeks after IUI and send the result to our infertility clinic.

If the result was positive, clinical pregnancy was confirmed by transvaginal ultrasound in the seventh week of amenorrhoea to verify the development of an appropriate intrauterine pregnancy.
two weeks after IUI

Collaborators and Investigators

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

Sponsor

Firat University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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)

June 1, 2021

Primary Completion (Actual)

November 3, 2022

Study Completion (Actual)

November 3, 2022

Study Registration Dates

First Submitted

June 24, 2026

First Submitted That Met QC Criteria

June 24, 2026

First Posted (Actual)

June 30, 2026

Study Record Updates

Last Update Posted (Actual)

June 30, 2026

Last Update Submitted That Met QC Criteria

June 24, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • 2021/07-16

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

If needed, the research supervisor can be contacted via email.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

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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