Development of the fetal tongue between 14 and 26 weeks of gestation: in utero ultrasonographic measurements

Abstract

Our objective was to establish nomograms for fetal tongue measurements from 14 weeks until mid-gestation by using transvaginal and transabdominal high-resolution ultrasound techniques. A prospective, cross-sectional study was performed on 120 normal singleton pregnancies between 14 and 26 weeks of gestation. Tongue circumference was measured by transvaginal ultrasonography between 14 and 17 weeks, and by abdominal ultrasound between 18 and 26 weeks of gestation. Fetal tongue circumference, as a function of gestational age, was expressed by the regression equation: tongue circumference (mm) = -23.9 + 3.75 x gestational age (weeks). The correlation, r2 = 0.95, was found to be highly statistically significant (p < 0.0001). The normal mean of tongue circumference per week and the 95% prediction limits were defined. During the study period we evaluated two cases with tongue circumference outside these 95% confidence limits: one had microglossia, the other macroglossia, and both were found to be associated with abnormal fetal karyotype. The presented normative data may be helpful in the prenatal diagnosis of suspected congenital syndromes that include, among their manifestations, tongue growth disturbances.

Transvaginal sonographic measurement of fetal lingual width in early pregnancy

“…A linear relationship between lingual width and gestational age was demonstrated. Very recently Achiron et al (1997) found a linear relationship between lingual circumference and gestational age. However, because the proximal border of the tongue cannot accurately be determined we believe measurements of the lingual width are more reliable compared with measurements of the lingual length or circumference.…”

“…However, because the proximal border of the tongue cannot accurately be determined we believe measurements of the lingual width are more reliable compared with measurements of the lingual length or circumference. In the study of Achiron et al (1997) two abnormal fetuses were evaluated at 24 weeks' gestation. One fetus with trisomy 21 had macroglossia, and the second with partial trisomy 1 had microglossia.…”

“…To date there is only one study on fetal tongue circumference in the first half of pregnancy (Achiron et al, 1997). However, since the proximal lingual edge has no well-defined border, an accurate measurement of the length of the tongue is difficult or even impossible.…”

Prenatal Mouth Movements: Can We Identify Co-Ordinated Fetal Mouth and LIP Actions Necessary for Feeding?

“…A number of studies have documented the development of oro-facial movements in the fetus (e.g., [10–15]), including mouth opening which has been observed in the fetus at 7 to 8 weeks of gestation, sucking at 15 weeks, and swallowing of amniotic fluid at 12 to 14 weeks. Yan et al ([14]: page 112) defined sucking, observed in 6 out of 10 fetuses once or twice as “a series of movements of the jaws accompanied by the sinking of the cheeks toward the oral cavity, with the fingers always in the mouth.” This contrasts with our observations of the unobstructed fetal face which did not include any stimulation of the oral region.…”

“…Yan et al ([14]: page 112) defined sucking, observed in 6 out of 10 fetuses once or twice as “a series of movements of the jaws accompanied by the sinking of the cheeks toward the oral cavity, with the fingers always in the mouth.” This contrasts with our observations of the unobstructed fetal face which did not include any stimulation of the oral region. Additionally, some researchers have examined jaw and tongue movements (e.g., [15]). Mizuno and Udea [4] assessed sucking performance in premature infants weekly between 24 to 36 weeks postconceptual age and suggested that the normative data collected on healthy premature infants could serve as a measure to identify preterm infants with sucking difficulties.…”