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Updated: Jun 24, 2026
07:04
A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse
Published on: October 24, 2017
Dating and growth in the first trimester.
Cecilia Bottomley1, Tom Bourne
1St George's University of London, Cranmer Terrace, London, UK. ceciliabottomley@doctors.org.uk
Best Practice & Research. Clinical Obstetrics & Gynaecology
|March 14, 2009
Summary
First trimester ultrasound dating accurately determines gestational age within 3-5 days. Early fetal size measurements can predict miscarriage and later pregnancy complications.
Area of Science:
- Obstetrics and Gynecology
- Prenatal Diagnostics
- Fetal Medicine
Background:
- Accurate gestational age determination is crucial for prenatal care.
- First-trimester ultrasound dating is recommended for all spontaneous pregnancies.
- First-trimester fetal growth is influenced by maternal and fetal factors.
Purpose of the Study:
- To evaluate the accuracy of first-trimester ultrasound for gestational age determination.
- To investigate the predictive value of early fetal size for pregnancy outcomes.
- To assess the relationship between first-trimester growth and adverse pregnancy events.
Main Methods:
- Utilizing transvaginal and transabdominal ultrasound scans to measure embryonic and fetal size.
- Employing crown-rump length measurements for dating.
- Analyzing cross-sectional and serial growth data from the first trimester.
Main Results:
- First-trimester ultrasound dating using crown-rump length is accurate to within 3-5 days.
- Early fetal growth restriction is associated with first-trimester miscarriage and chromosomal abnormalities.
- Small size at 11-14 week scans predicts later intrauterine growth restriction, preeclampsia, and preterm delivery.
Conclusions:
- First-trimester ultrasound dating is a reliable method for determining gestational age.
- Early fetal growth assessment in the first trimester can identify pregnancies at risk for miscarriage and adverse outcomes.
- Ultrasound measurements provide valuable insights into early pregnancy development and potential complications.
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