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Murine Fetal Echocardiography
Published on: February 15, 2013
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Biparietal diameter for first-trimester pregnancy dating: multicenter cohort study.
C de Paco Matallana1,2, V Rolle3,4, A M Fidalgo5,6
1Department of Obstetrics and Gynecology, Hospital Clínico Universitario 'Virgen de la Arrixaca', El Palmar, Murcia, Spain; Institute for Biomedical Research of Murcia, IMIB-Arrixaca, El Palmar, Murcia, Spain.
Summary
Fetal biparietal diameter (BPD) measurements offer a reliable alternative for pregnancy dating at 11-13 weeks gestation compared to crown-rump length (CRL). This new BPD formula improves accuracy and reduces post-term pregnancy induction rates.
Area of Science:
- Maternal-fetal medicine
- Prenatal diagnostics
- Ultrasound biometry
Background:
- Accurate pregnancy dating is crucial for optimal prenatal care and management.
- Crown-rump length (CRL) is the standard for early pregnancy dating (11-13 weeks), but biparietal diameter (BPD) may offer an alternative.
- Existing BPD-based dating formulas have shown limitations in accuracy.
Purpose of the Study:
- To evaluate the accuracy of fetal biparietal diameter (BPD) measurement for pregnancy dating between 11 and 13 weeks' gestation.
- To compare the accuracy of a newly developed BPD-based formula against established CRL and BPD formulas.
- To assess the impact of different dating methods on the rate of post-term pregnancy induction.
Main Methods:
- Retrospective multicenter cohort study involving 49,492 women across five European maternity units (2011-2019).
- Development of a new BPD-based pregnancy dating formula using linear regression on in-vitro fertilization (IVF) conceived pregnancies.
- Internal and external validation of the new formula, compared with Robinson's CRL and Kustermann's BPD formulas using Euclidean distance, relative absolute error, and mean squared error.
Main Results:
- The newly developed BPD formula demonstrated high accuracy in internal validation (mean difference 0.0006 days vs. conception date), outperforming Kustermann's (-0.31 days) and Robinson's (-1.78 days) formulas.
- External validation showed the new BPD formula and Kustermann's formula underestimated gestational age compared to Robinson's formula (-1.25 days and -0.96 days, respectively).
- Pregnancy dating using the new BPD formula or Kustermann's formula resulted in significantly lower rates of post-term pregnancy induction (6.8% and 7.0%) compared to Robinson's formula (8.1%).
Conclusions:
- Fetal biparietal diameter (BPD) measurement provides a reliable and accurate alternative for pregnancy dating between 11 and 13 weeks' gestation.
- The newly developed BPD formula offers improved accuracy and potentially reduces unnecessary post-term pregnancy inductions.
- Ultrasound-based BPD measurement is a viable option for early pregnancy dating, complementing CRL measurements.
