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Updated: Aug 11, 2026
A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse
Published on: October 24, 2017
The fetal mandible: an in utero sonographic evaluation between 11 and 31 weeks' gestation
Yaron Zalel1, Liat Gindes, Reuven Achiron
1Department of Obstetrics and Gynecology, The Chaim Sheba Medical Center, Tel-Hashomer, Tel-Aviv University, Ramat Gan, Israel. zalel_y@netvision.net.il
Objective:
To construct a growth chart of the mandible throughout gestation.
Methods:
A prospective cross-sectional study of normal singleton pregnancies was conducted. Measurements of the fetal mandibular transverse and antero-posterior diameters were performed with high-resolution transvaginal and transabdominal ultrasonography in 490 pregnant women with singleton low-risk pregnancies between 11 and 31 weeks' gestation.
Results:
The mandibular transverse and antero-posterior diameters were recorded by week of gestation and the ratio was calculated: mandibular ratio (MR) = 1.7759 - 0.01047 x gestational week. There was a negative linear correlation (-1.047%) for each incoming week of gestation. Normal values (+/-1SD and 2SD) were established.
Conclusion:
The present data provides a normal range of fetal mandibular diameters during normal pregnancies and introduces a new parameter, the mandibular ratio, for the intrauterine assessment of the fetal mandibular development.
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