Twin to Twin TransfusionNCT06829901
The Effect of Uterine Entry In Fetoscopic Laser Photocoagulation for Twin-To-Twin Transfusion Syndrome
A study testing Fetoscopic Laser Photocoagulation in people with Twin to Twin Transfusion, run by Baylor College of Medicine at 1 site in United States.
Trial summary
The purpose of this study is to evaluate whether the entry technique surgeons use to get inside the uterus to perform fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome has an effect on the rates of chorioamniotic membrane separation. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Twin to Twin Transfusion
- What is being tested?
- Fetoscopic Laser Photocoagulation
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 216 participants
- Where
- 1 siteUnited States
- Study dates
- 14 Mar 2025to Dec 2030
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients who are eligible and elect to undergo fetoscopic selective laser photocoagulation for complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome.
- Patients will be between 16 0/7 weeks and 26 0/7 weeks gestational age.
Who cannot join
- Patients who do not elect to undergo fetoscopic laser photocoagulation for the treatment of complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome.
- Triplets and higher order multiple gestations.
- Patients who are less than 16 0/7 weeks or greater than 26 0/7 weeks gestational age.
- Patients with a short cervix (less than 1.5 cm).
- Patients with a known subchorionic hemorrhage.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Texas Children's Hospital - Pavilion for Women
Houston, Texas, 77030
Michael Belfort, MD, PhD, 832-826-7375, belfort@bcm.edu
Becky Johnson, MS, CCRP, 832-826-7451, rj2@bcm.edu
About this study
Official title: The Effect of Entry Technique on Chorioamniotic Membrane Separation in Fetoscopic Laser Photocoagulation for Twin-To-Twin Transfusion Syndrome
The purpose of this study is to evaluate whether the entry technique surgeons use to get inside the uterus to perform fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome has an effect on the rates of chorioamniotic membrane separation.
Read the detailed description
Patients who choose to undergo fetoscopic selective laser photocoagulation (SFLP) at Texas Children's Fetal Center will be offered participation in this research study by study investigators. Description of study rationale and design and a focused interview by the study coordinator to afford potential participants a formal opportunity to examine what they have learned about the research study in the course of their evaluation and discuss how they feel about enrolling in the research study. Once the patient is deemed eligible the informed consent process will be reviewed. If patients elect to participate in the study, informed consent will be obtained, and participants will be provided a copy of the signed consent.
After consent has been obtained, participants will be randomized into two groups ("direct entry" and "Seldinger technique").
Procedure: Selective laser photocoagulation (SFLP) is standard of care for the treatment of complicated monochorionic twin pregnancies. Entry into the uterus for SFLP is achieved under ultrasound guidance using one of two accepted methods, direct entry or the Seldinger technique. Intravenous sedation with local anesthesia at the site of insertion has been found to provide sufficient maternal anesthesia for the procedure.
Group I - Direct entry: The surgeon will gain access to the uterus by inserting a sharp trocar through a small incision in the skin. After access has been established, the trocar is removed and a small tube called a cannula is left in place.
Group II - Seldinger technique: The surgeon will gain access to the uterus by inserting needle through a small incision in the skin and run a guide wire through the needle so a thin tube called a cannula can be placed over the wire.
Follow-Up:
Participants will be monitored after the procedure and upon discharge from the hospital they are free to resume care with their primary doctor. Investigators will collect follow-up data on the health of the participant and the babies until the babies turn one month old.
- Conditions
- Twin to Twin Transfusion
- Being tested
- Fetoscopic Laser Photocoagulation
- Keywords
- fetoscopic laser photocoagulation, TTTS, uterine entry, direct entry, Seldinger technique, chorioamniotic membrane separation, CAS
- Medical subject headings
- Fetofetal Transfusion
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fetoscopic Laser PhotocoagulationProcedure or surgery
Patients who choose to undergo fetoscopic selective laser photocoagulation for complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome will be offered participation in the study. All participants will undergo selective laser photocoagulation and entry into the uterus will be achieved using one of two accepted methods, either direct entry or the Seldinger technique.
| Study group | Role | What they receive |
|---|---|---|
| Direct Entry | Active comparator | Surgeons will access the uterus to perform fetoscopic laser photocoagulation by inserting a sharp trocar through a small incision in the skin. The trocar is then removed and a small tube called a cannula is left in place. Receives: Procedure: Fetoscopic Laser Photocoagulation |
| Seldinger Technique | Active comparator | Surgeons will access the uterus to perform fetoscopic laser photocoagulation by inserting needle through a small incision in the skin and running a guide wire through the needle so a thin tube called a cannula can be placed over the wire. Receives: Procedure: Fetoscopic Laser Photocoagulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Rate of Immediate Chorioamniotic Membrane Separation (CAS)
Number of participants that have chorioamniotic membrane separation within 24 hours of the procedure.
Measured: Up to hospital discharge post-procedure (up to 5 days)
Secondary outcomes (8)
Rate of Chorioamniotic Membrane Separation (CAS)
Number of participants that have chorioamniotic membrane separation outside the first 24 hours hours following the procedure
Measured: From the post-surgical period (outside the first 24 hours) until delivery, up to 25 weeks
Gestational Age at Delivery
Gestational age at the time of delivery
Measured: At delivery
Preterm Birth
Number of participants that deliver at <37 weeks gestation
Measured: At delivery
Procedure to Delivery Interval
Days between the participant's procedure and when the babies are delivered
Measured: At delivery
Placental Abruption
As measured by presence in medical record
Measured: Up to hospital discharge post-procedure (up to 5 days)
Chorioamnionitis
As measured by presence in medical record
Measured: Up to hospital discharge post-procedure (up to 5 days)
Septostomy
As measured by presence in medical record
Measured: Up to hospital discharge post-procedure (up to 5 days)
Preterm Premature Rupture of Membranes (PPROM)
As measured by presence in medical record
Measured: At delivery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Feb 2025
- Study start14 Mar 2025
- Primary completionDec 2029 (estimated)
- Study completionDec 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Twin to Twin TransfusionStudies of the same condition, open and under way.
- More trials run by Baylor College of MedicineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 216 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Baylor College of Medicine
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ahmed Nassr, Baylor College of Medicine
- Investigators
- Ahmed Nassr, MD, PhD, Principal investigator, Baylor College of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06829901
- Sponsor's protocol ID
- H-56175
- Status last verified
- Mar 2026
- First submitted
- 31 Jan 2025
- Last updated
- 4 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Burnett BA, Munoz JL, Johnson RM, Parobek CM, Delgadillo Chabolla LE, Buskmiller C, Donepudi RV, Sanz Cortes M, Belfort MA, Nassr AA. The effect of uterine entry technique on chorioamniotic membrane separation in fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome: protocol for a randomized controlled trial. BMC Pregnancy Childbirth. 2025 Nov 21;25(1):1253. doi: 10.1186/s12884-025-08410-5.
PubMed 41272584
Study at a glance
From the registry record, last updated by the sponsor on 4 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Entry Technique on Chorioamniotic Membrane Separation in Fetoscopic Laser Photocoagulation for Twin-To-Twin Transfusion Syndrome
- ClinicalTrials.gov ID
- NCT06829901
- Acronym / sponsor ID
- H-56175
- Conditions
- Twin to Twin Transfusion
- Keywords
- fetoscopic laser photocoagulation, TTTS, uterine entry, direct entry, Seldinger technique, chorioamniotic membrane separation, CAS
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 216 participants (estimated)
- Lead sponsor
- Baylor College of MedicineUniversity, hospital or other
- Study start
- 14 Mar 2025 (actual)
- Primary completion
- Dec 2029 (estimated)
- Study completion
- Dec 2030 (estimated)
- First posted
- 17 Feb 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to evaluate whether the entry technique surgeons use to get inside the uterus to perform fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome has an effect on the rates of chorioamniotic membrane separation.
Detailed description
Patients who choose to undergo fetoscopic selective laser photocoagulation (SFLP) at Texas Children's Fetal Center will be offered participation in this research study by study investigators. Description of study rationale and design and a focused interview by the study coordinator to afford potential participants a formal opportunity to examine what they have learned about the research study in the course of their evaluation and discuss how they feel about enrolling in the research study. Once the patient is deemed eligible the informed consent process will be reviewed. If patients elect to participate in the study, informed consent will be obtained, and participants will be provided a copy of the signed consent.
After consent has been obtained, participants will be randomized into two groups ("direct entry" and "Seldinger technique").
Procedure: Selective laser photocoagulation (SFLP) is standard of care for the treatment of complicated monochorionic twin pregnancies. Entry into the uterus for SFLP is achieved under ultrasound guidance using one of two accepted methods, direct entry or the Seldinger technique. Intravenous sedation with local anesthesia at the site of insertion has been found to provide sufficient maternal anesthesia for the procedure.
Group I - Direct entry: The surgeon will gain access to the uterus by inserting a sharp trocar through a small incision in the skin. After access has been established, the trocar is removed and a small tube called a cannula is left in place.
Group II - Seldinger technique: The surgeon will gain access to the uterus by inserting needle through a small incision in the skin and run a guide wire through the needle so a thin tube called a cannula can be placed over the wire.
Follow-Up:
Participants will be monitored after the procedure and upon discharge from the hospital they are free to resume care with their primary doctor. Investigators will collect follow-up data on the health of the participant and the babies until the babies turn one month old.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Direct Entry | Active comparator | Procedure: Fetoscopic Laser PhotocoagulationSurgeons will access the uterus to perform fetoscopic laser photocoagulation by inserting a sharp trocar through a small incision in the skin. The trocar is then removed and a small tube called a cannula is left in place. |
| Seldinger Technique | Active comparator | Procedure: Fetoscopic Laser PhotocoagulationSurgeons will access the uterus to perform fetoscopic laser photocoagulation by inserting needle through a small incision in the skin and running a guide wire through the needle so a thin tube called a cannula can be placed over the wire. |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Patients who are eligible and elect to undergo fetoscopic selective laser photocoagulation for complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome.
- Patients will be between 16 0/7 weeks and 26 0/7 weeks gestational age.
Key exclusion criteria (5 listed)
- Patients who do not elect to undergo fetoscopic laser photocoagulation for the treatment of complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome.
- Triplets and higher order multiple gestations.
- Patients who are less than 16 0/7 weeks or greater than 26 0/7 weeks gestational age.
- Patients with a short cervix (less than 1.5 cm).
- Patients with a known subchorionic hemorrhage.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fetoscopic Laser PhotocoagulationPatients who choose to undergo fetoscopic selective laser photocoagulation for complicated monochorionic-diamniotic twin pregnancies with twin-to-twin transfusion syndrome will be offered participation in the study. All participants will undergo selective laser photocoagulation and entry into the uterus will be achieved using one of two accepted methods, either direct entry or the Seldinger technique. | Procedure or surgery | Direct Entry, Seldinger Technique |
Primary outcome
Rate of Immediate Chorioamniotic Membrane Separation (CAS)
Time frame: Up to hospital discharge post-procedure (up to 5 days)
Number of participants that have chorioamniotic membrane separation within 24 hours of the procedure.
8 secondary outcomes
Rate of Chorioamniotic Membrane Separation (CAS)
Time frame: From the post-surgical period (outside the first 24 hours) until delivery, up to 25 weeks
Gestational Age at Delivery
Time frame: At delivery
Preterm Birth
Time frame: At delivery
Procedure to Delivery Interval
Time frame: At delivery
Placental Abruption
Time frame: Up to hospital discharge post-procedure (up to 5 days)
Chorioamnionitis
Time frame: Up to hospital discharge post-procedure (up to 5 days)
Septostomy
Time frame: Up to hospital discharge post-procedure (up to 5 days)
Preterm Premature Rupture of Membranes (PPROM)
Time frame: At delivery
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Mar 2026.
- Derived from this study: PubMed 41272584Burnett BA, Munoz JL, Johnson RM, Parobek CM, Delgadillo Chabolla LE, Buskmiller C, Donepudi RV, Sanz Cortes M, Belfort MA, Nassr AA. The effect of uterine entry technique on chorioamniotic membrane separation in fetoscopic laser photocoagulation for twin-to-twin transfusion syndrome: protocol for a randomized controlled trial. BMC Pregnancy Childbirth. 2025 Nov 21;25(1):1253. doi: 10.1186/s12884-025-08410-5.
Related trials for Twin to Twin Transfusion
Not yet recruiting
MoDi Twin Placental Imaging
Monochorionic Diamniotic Placenta, Monochorial Monoamniotic Placenta
Active, not recruitingObservational study
Database of Monochorionic Pregnancies
Monochorionic Diamniotic Placenta, Monochorial Monoamniotic Placenta
RecruitingObservational study
Fetal Electrophysiologic Abnormalities in High-Risk Pregnancies Associated With Fetal Demise
High Risk Pregnancy, Congenital Heart Disease
Not yet recruiting
The Efficacy of the KARL STORZ Curved Fetoscope and Straight Fetoscope for Laser Photocoagulation of Placental Anastomoses
Twin to Twin Transfusion Syndrome
Recruiting
Evaluation of Laparotomy With Trans-Amniotic Suture Placement in TTTS Surgery
Twin to Twin Transfusion Syndrome, Twin Anemia-Polycythemia Sequence
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Ahmed Nassr, MD, PhD principal investigator
Baylor College of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Fetoscopic Laser Photocoagulation in people with Twin to Twin Transfusion, run by Baylor College of Medicine at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 4 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ahmed Nassr, MD, PhD (832-826-7449, ahmed.nassr@bcm.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Rate of Immediate Chorioamniotic Membrane Separation (CAS) (time frame: Up to hospital discharge post-procedure (up to 5 days)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06829901, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Mar 2026.