Using fetal transverse thalamic diameter on 2D ultrasound to help estimate gestational age and growth
The Reliability of Measuring Transverse Thalamic Diameter in Determining the Gestational Age as a Fetal Growth Parameter Using 2D Ultrasound
This project tests whether measuring the baby’s transverse thalamic diameter with routine 2D abdominal ultrasound can help estimate gestational age and track fetal growth in single pregnancies between 18 and 36 weeks.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 110 (estimated) |
| Sex | Female |
| Sponsor | Cairo University Academic / other |
| Locations | 1 site (Giza, Cairo Governorate) |
| Trial ID | NCT07169929 on ClinicalTrials.gov |
What this trial studies
This observational study measures the transverse thalamic diameter (TTD) on 2D abdominal ultrasound in pregnant people between 18 and 36 weeks and compares TTD to gestational age, head circumference, and trans-cerebellar diameter. Measurements follow a standardized ‘‘guitar-shaped’’ plane that prior work has shown gives reproducible thalamic diameter values, and automatic measurement tools have been described. Participants with unknown dates, first-trimester CRL missing, BMI >35, maternal systemic disease (diabetes, hypertension, SLE), fetal CNS anomalies, multiple pregnancy, or exposure to CNS-acting drugs are excluded. Results will be used to produce normal-range thalamic charts and explore whether echogenic thalamus features relate to other fetal maturity markers.
Who should consider this trial
Good fit: Ideal candidates are pregnant people with a singleton pregnancy between 18 and 36 weeks who have reliable dating (first-trimester CRL) and no major maternal diseases, obesity (BMI >35), fetal CNS anomalies, multiple pregnancy, or CNS-acting drug exposure.
Not a fit: People with multiple pregnancies, uncertain or undated gestation without an early CRL, high BMI over 35, known maternal diabetes/hypertension/SLE, fetal CNS anomalies, or current use of opiates/CNS drugs are excluded and unlikely to benefit from these measurements.
Why it matters
Potential benefit: If successful, this could provide a simple additional ultrasound measurement to improve estimation of gestational age and help monitor fetal growth.
How similar studies have performed: Prior published work (including Sridar et al. 2016 and 2020) has shown a linear increase of transverse thalamic diameter with gestational age and good reproducibility and measurement accuracy using similar 2D ultrasound methods.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * All pregnant women with singleton pregnancy with gestational age between 18 to 36 weeks Exclusion Criteria: * Women who are not sure of dates and don't have an US report with CRL measured in the first trimester * Maternal obesity (BMI\>35) as abdominal fat cause restriction in taking measurement * Known case of DM or Hypertension or SLE * Any fetal head or CNS anomalies * Any maternal opiates and CNS drugs (methadone) IUGR * Twins or multiple pregnancy
Where this trial is running
Giza, Cairo Governorate
- Shaimaa El Shemy — Giza, Cairo Governorate, Egypt (Recruiting)
Study contacts
- Study coordinator: Shaimaa El Shemy, MD
- Email: sh.elshemy@gmail.com
- Phone: 01220632263
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.