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Updated: Jul 29, 2026
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Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
First-trimester growth patterns of aneuploid fetuses
G Schemmer1, R J Wapner, A Johnson
1Jefferson Medical College, Thomas Jefferson University, Department of Obstetrics and Gynecology, Philadelphia, PA 19107, USA.
Prenatal Diagnosis
|February 1, 1997
Summary
First-trimester growth restriction is linked to specific fetal aneuploidies like trisomy 18 and 13. Early growth rate, not just crown-rump length, helps identify these chromosomal abnormalities.
Area of Science:
- Prenatal genetics and diagnostics
- Fetal development and growth assessment
Background:
- First-trimester growth restriction has been observed in some aneuploid pregnancies.
- Understanding early fetal growth patterns in chromosomal abnormalities is crucial for diagnostic advancements.
Purpose of the Study:
- To investigate the association between first-trimester fetal growth parameters and aneuploidy.
- To compare crown-rump lengths (CRLs) and growth rates in chromosomally abnormal versus euploid fetuses.
Main Methods:
- Comparison of CRLs and growth rates between 196 aneuploid fetuses and 1929 euploid controls.
- Analysis included fetuses with trisomy 18, trisomy 13, triploidy, trisomy 21, sex chromosome trisomies, and 45,X.
- Evaluation of growth rate versus single CRL measurement as discriminators for aneuploidy.
Main Results:
- Significantly reduced mean CRLs and growth rates were found in fetuses with trisomy 18, trisomy 13, and triploidy (P < 0.05).
- Fetal growth rate, using a fifth percentile cut-off, was a better indicator than CRL alone for identifying these aneuploidies.
- No significant growth reductions were observed in fetuses with trisomy 21, sex chromosome trisomies, or 45,X.
Conclusions:
- Fetal growth restriction can manifest in the first trimester due to underlying chromosomal abnormalities.
- This growth restriction is attributed to intrinsic fetal factors, not delayed ovulation.
- These findings are vital for refining first-trimester serum screening protocols.
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