An observational study in Twin Twin Transfusion Syndrome, sponsored by Columbia University. Completed at 1 site in United States. Open to female participants. Per ClinicalTrials.gov, last updated 2018-07-18.
Sponsored by Columbia University · Observational
Among 22 studies in Fetofetal Transfusion with a site in United States — 7 open to participants now, 8 under way, none of them phase 3. Fetofetal Transfusion · United States.
Among the 22 studies in Fetofetal Transfusion with a site in United States, this one is one of 2 that started in 2016, is one of 8 observational ones, and was the 10th registered.
47 studies on the registry are indexed under Fetofetal Transfusion; 10 are open to participants now.
Browse Fetofetal Transfusion studies →7 of the 22 studies in Fetofetal Transfusion with a site in United States are open now. Recruiting first, the newest first:
Baylor College of Medicine · Sites in United States
Children's Hospital Medical Center, Cincinnati · Sites in United States
Boston Children's Hospital · Sites in United States
Seattle Children's Hospital · Sites in United States
Medical College of Wisconsin · Sites in United States
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 8 Fetofetal Transfusion studies recruiting now, 5 (63%) set no upper age limit and 3 (38%) stop at 75 or younger; 4 take children under 18; 1 take healthy volunteers.
This study: female.
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22 studies; the count open now beside each. This study's row is marked.
First in 2002; this study’s year is marked. 2 started in 2016.
This study's enrollment of 24 is below the median of 104 across 14 observational studies indexed under Fetofetal Transfusion.
Median enrollment 55 across the 14 interventional studies, 64 across the 8 observational. Of the 11 that completed or were terminated, 0 (0%) have results posted.
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1 of 22 have an industry lead sponsor. The 10 most frequent:
Columbia University is the lead sponsor of 1,136 studies on the registry; 195 are open to participants now.
Of its 180 completed or terminated interventional studies of FDA-regulated products, 148 (82%) have results posted.
Columbia University has 1 study filed under Fetofetal Transfusion — fewer than ten, so there is no comparison to draw.
1 of the studies in Fetofetal Transfusion with a site in United States that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT06056635Boston Children's HospitalA Prospective Study on the Role of Karl Storz Curved and Straight Fetoscopes (11508AAK and 11506AAK) for Fetoscopic Intrauterine Procedures | 2026-12-01 |
Among the 22 studies in Fetofetal Transfusion with a site in United States, from their registry updates:
Nothing recorded among them since 2026-09-25.
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Twin-twin transfusion syndrome (TTTS) is a complication affecting 10-15% of monochorionic, diamniotic (MCDA) twin pregnancies. Unevenly distributed blood flow across a shared placental circulation results in a volume-restricted donor twin and a volume-overloaded recipient twin, and TTTS has high perinatal morbidity and mortality without treatment.
Differential donor and recipient findings in TTTS can be observed upon ultrasound evaluation. TTTS is classified according to the Quintero staging system, which evaluates amniotic fluid volumes, fetal bladders, Doppler study of the umbilical artery and ductus venosus, and for the presence of hydrops or death. However, due to seemingly complex and variable disease pathophysiology, the Quintero system cannot predict outcomes on a case-by-case basis.
Prior studies have associated fetal renal artery Doppler ultrasound measurements with amniotic fluid volume in singleton pregnancies. In fetuses with placental insufficiency, adaptive circulatory changes maintain adequate oxygen delivery to vital organs such as the heart, brain, and adrenals, with a consequent deprivation to splanchnic organs. In the fetal kidney, as vascular resistance increases during hypoxia, renal perfusion decreases proportionately. These changes are reflected in renal artery Doppler findings. As these same adaptations are believed to occur in donor twins, renal artery Doppler studies may also be of value in the TTTS evaluation.
This study plans to perform renal artery Doppler assessments in MCDA twins complicated by TTTS, and compare them to measurements in gestational-age equivalent MCDA twins without TTTS. If findings differ significantly, it would support further investigation into the use of renal artery Doppler studies for the evaluation of complicated MCDA twins.
TTTS, which complicates 10-15% of MCDA twin pregnancies, is characterized by a net imbalance of volume between twins, mediated through abnormal placental blood vessel anastomoses that connect the two placental circulations. Clinically, the "donor" twin develops features of anemia and hypovolemia, while the "recipient" twin shows signs of hypervolemia and hypertensive fluid overload. If untreated, the syndrome has a perinatal mortality rate as high as 80-100%. Although modern intrauterine therapies have improved the rates of fetal death, significant risks of morbidity and mortality remain even after treatment.
Twin-twin transfusion syndrome is most commonly classified according to a staging system developed by Quintero et al in 1999, which is based on discrete, categorical ultrasound findings (amniotic fluid volume, presence/absence of a fetal bladder, umbilical artery Doppler studies, fetal hydrops, and death). The system includes 5 stages ranging from mild disease with isolated discordant amniotic fluid volumes, to severe disease with demise of one or both twins. Although this system has some prognostic value, it also has significant limitations due to the highly complex physiologic conditions that are involved in the disease. For example, some criteria in the staging system are not consistently representative of fetal physiology. Additionally, the stages do not correlate well with overall perinatal survival or with outcomes following intrauterine therapies.
Recent work has demonstrated that the complex pathophysiology of twin-twin transfusion syndrome involves a discordant activation of the renin angiotensin system (RAS). RAS is normally important in fluid and salt regulation in both the adult and the fetus, and TTTS in marked hypovolemia and hypervolemia in monozygous fetuses within the same maternal environment. The renal RAS in the donor is up-regulated, presumably as a consequence of hypovolemia. The recipient is also exposed to high levels or RAS components, either due to the transfusion of these components from the donor via anastomoses, or via discordant placental RAS activation, resulting in a hypertensive, hypervolemic state.
Multiple studies have identified a correlation between Doppler assessment of the fetal renal artery and the development of oligohydramnios, a hypovolemic state, in singleton pregnancies. However, the use of renal artery Doppler studies has not yet been fully evaluated in twin gestations. In particular, it has not been evaluated in MCDA twin gestations complicated by TTTS, the pathophysiology of which involves significant alterations in fetal volume and fluid status.
This project is intended to serve as a single-center study to determine if there is indeed a difference in renal artery Doppler parameters in sets of MCDA twins with TTTS compared to sets of MCDA twins without TTTS. The identification of a significant difference would potentially provide support for further investigation into this measurement as a screening tool or prognostic indicator when applied to MCDA twin pregnancies.
Secondary goals of this study include: comparing donor to recipient renal artery Doppler findings among pregnancies with TTTS, evaluating serial renal artery Doppler findings over time per pregnancy, and evaluating pre- and post-therapy renal artery Doppler findings in those pregnancies undergoing therapy for TTTS.
The subject population will consist of pregnant women with monochorionic / diamniotic (MCDA) twin pregnancies with and without twin-twin transfusion syndrome (TTTS). This population is selected in order to investigate twin-twin transfusion syndrome, which is a disease process that is unique to pregnancies with monochorionic / diamniotic twins. Patients will be included in the study if they have a diagnosis of a MCDA twin gestation beyond the first trimester or pregnancy (greater than 14 weeks gestation).
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Cases of monochorionic / diamniotic twin pregnancies diagnosed with twin-twin transfusion syndrome.
Diagnostic Test: Doppler ultrasound of fetal renal artery
Controls of monochorionic / diamniotic twin pregnancies without a diagnosis of twin-twin transfusion syndrome.
Diagnostic Test: Doppler ultrasound of fetal renal artery
Doppler ultrasound assessment of the proximal fetal renal artery to with measurement of the peak systolic velocity, resistive index, pulsatility index, and systolic/diastolic ratio.
Fetal renal artery Doppler PSV for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the peak systolic velocity for twin A.
Time frame: Obtained at the time of enrollment.
Fetal renal artery Doppler RI for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the resistive index for twin A.
Time frame: Obtained at the time of enrollment.
Fetal renal artery Doppler PI for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the pulsatility index for twin A.
Time frame: Obtained at the time of enrollment.
Fetal renal artery Doppler PSV for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the peak systolic velocity for twin B.
Time frame: Obtained at the time of enrollment.
Fetal renal artery Doppler RI for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the resistive index for twin B.
Time frame: Obtained at the time of enrollment.
Fetal renal artery Doppler PI for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the pulsatility index for twin B.
Time frame: Obtained at the time of enrollment.
Post-laser fetal renal artery Doppler PSV for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the peak systolic velocity for twin A.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Post-laser fetal renal artery Doppler RI for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the resistive index for twin A.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Post-laser fetal renal artery Doppler PI for twin A
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the pulsatility index for twin A.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Post-laser fetal renal artery Doppler PSV for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the peak systolic velocity for twin B.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Post-laser fetal renal artery Doppler RI for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the resistive index for twin B.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Post-laser fetal renal artery Doppler PI for twin B
Doppler ultrasound assessment of the proximal fetal renal artery with measurement of the pulsatility index for twin B.
Time frame: Obtained within one week following fetoscopic laser therapy for cases in which this treatment is provided.
Plan to share: No — There is no plan to share individual participant data with other researchers.
Ran from Sep 2016 to primary completion in Mar 2018, 18 months.
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This study is completed, as verified in Jul 2018. You cannot join it, but the record below documents what was studied.
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