NCT07164001

Twins With Specific vs. Traditional Fetal Growth Charts

Twins With Specific vs. Traditional Fetal Growth Charts (TWiST): A Randomized Controlled Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 150 (estimated)
• Sponsor: Indiana University · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study aims to compare how well two different types of fetal growth charts work in tracking the growth of twins during pregnancy. These charts help doctors decide if a fetus is growing normally. One type is commonly used for all pregnancies, while the other is specially designed for twin pregnancies. The study will enroll pregnant individuals carrying twins. Participants will be randomly assigned to have their care guided by either the traditional chart or the twin-specific chart. Researchers will compare outcomes such as birth weight, timing of delivery, and newborn health. The goal is to find out if using twin-specific charts can improve care and reduce unnecessary interventions.

Detailed description

Twin pregnancies are at increased risk for growth abnormalities and adverse perinatal outcomes. Despite physiological differences in fetal growth patterns between singleton and twin pregnancies, most clinical decisions in the United States still rely on singleton-based fetal growth charts. This randomized controlled trial (RCT) evaluates whether using twin-specific fetal growth charts to guide clinical care results in better perinatal outcomes compared to using standard singleton-based charts. Participants will be pregnant individuals with twin gestations receiving routine prenatal care at participating clinical sites. Eligible participants will be randomized to one of two groups: (1) management based on singleton growth charts or (2) management based on twin-specific charts. Both charts will be used to assess fetal growth during ultrasound visits, but only the chart assigned to the participant's group will inform clinical decision-making. Data will be collected on outcomes including birth weight, small-for-gestational-age (SGA) classification, gestational age at delivery, NICU admissions, and neonatal morbidity. The study aims to determine whether using twin-specific fetal growth standards can reduce the overdiagnosis of growth restriction and the associated risks of iatrogenic preterm delivery and unnecessary interventions. Results may support more tailored approaches to growth assessment in twin pregnancies.

Conditions

• Twin Pregnancy

Interventions

Type	Name	Description
OTHER	Twin-Specific Growth Chart Interpretation	Participants in this arm will have their fetal growth assessed using twin-specific growth charts. These charts account for twin gestation norms and may influence clinical decision-making regarding growth restriction and perinatal management. The intervention does not involve any direct physical procedure or device but rather a change in the interpretation framework of routinely collected ultrasound data.
OTHER	Singleton-Based Growth Chart Interpretation	Participants in this arm will have their fetal growth assessed using singleton-based growth charts. These charts are commonly used in standard practice but may overestimate growth restriction in twin pregnancies. The intervention does not involve any direct physical procedure or device but alters the interpretation framework for standard prenatal ultrasound findings.

Timeline

• Start date: 2026-01-01
• Primary completion: 2029-12-31
• Completion: 2030-01-28
• First posted: 2025-09-09
• Last updated: 2025-09-15