Related Experiment Video
Updated: May 15, 2026
07:04
A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse
Published on: October 24, 2017
First-trimester prediction of birth weight
Isabelle Boucoiran1, Anissa Djemli, Catherine Taillefer
1Department of Obstetrics and Gynecology, CHU Sainte-Justine Research Center, Université de Montréal, Montreal, Quebec, Canada. isabelle@boucoiran.fr
American Journal of Perinatology
|January 4, 2013
Summary
First-trimester screening markers like nuchal translucency and PAPP-A can predict birth weight. However, their clinical use for identifying small-for-gestational-age (SGA) or large-for-gestational-age (LGA) babies is limited.
Area of Science:
- Maternal-fetal medicine
- Prenatal diagnostics
- Reproductive endocrinology
Background:
- First-trimester screening typically assesses aneuploidy risk using nuchal translucency (NT), free beta-chorionic gonadotropin (fβ-hCG), and pregnancy-associated plasma protein-A (PAPP-A).
- The potential of these markers to predict birth weight and identify fetuses at risk for small-for-gestational-age (SGA) or large-for-gestational-age (LGA) remains less understood.
Purpose of the Study:
- To investigate the predictive value of first-trimester aneuploidy screening parameters for birth weight.
- To determine if these parameters can significantly improve the detection of SGA and LGA neonates.
Main Methods:
- Retrospective cohort study of 4110 pregnancies.
- Measurement of NT, fβ-hCG, and PAPP-A between 11 and 13 weeks gestation.
- Exclusion of multiple pregnancies, chromosomal anomalies, major fetal defects, and early deliveries.
Main Results:
- NT and PAPP-A levels were significantly lower in SGA newborns compared to unaffected infants.
- NT levels were significantly higher in LGA newborns compared to unaffected infants.
- While first-trimester markers contributed to birth weight prediction in a multiple linear model, they did not significantly improve the prediction of SGA or LGA beyond maternal characteristics alone.
Conclusions:
- First-trimester screening parameters for aneuploidies demonstrate a contribution to birth weight prediction.
- The clinical utility of these markers for identifying pregnancies at risk for SGA or LGA babies is limited.
Related Concept Videos
01:52Regression Toward the Mean
Regression toward the mean (“RTM”) is a phenomenon in which extremely high or low values—for example, and individual’s blood pressure at a particular moment—appear closer to a group’s average upon remeasuring. Although this statistical peculiarity is the result of random error and chance, it has been problematic across various medical, scientific, financial and psychological applications. In particular, RTM, if not taken into account, can interfere when researchers try to extrapolate results...
01:17z Scores and Area Under the Curve
z scores are the standardized values obtained after converting a normal distribution into a standard normal distribution. A z score is measured in units of the standard deviation. The z score tells you how many standard deviations the value x is above (to the right of) or below (to the left of) the mean, μ. Values of x that are larger than the mean have positive z scores, and values of x that are smaller than the mean have negative z scores. If x equals the mean, then x has a z score of zero.