Fetal facial expressions in small-for-gestational-age and growth-restricted fetuses

Twin fetal facial expressions at 30-33+6 weeks of gestation

Objective To assess the characteristics of twin fetal facial expressions at 30-33 + 6 weeks of gestation using four-dimensional (4D) ultrasound to clarify twin fetal brain development and maturation. Methods Frequencies of seven fetal facial expressions were studied using 4D ultrasound for 15 minutes in 30 singleton pregnancies and 18 twin pregnancies [four monochorionic diamniotic (MD) and 14 dichorionic diamniotic (DD) twins] at 30-33 + 6 weeks of gestation. Comparison of the frequency in each facial expression was performed between singleton and twin fetuses. Results Mouthing was the most frequent facial expression at 30-33 + 6 weeks of gestation, followed by blinking in twin and singleton fetuses. Both facial expressions were significantly more frequent than other expressions (P < 0.05). The frequencies of mouthing and scowling in twin fetuses were significantly lower than those in singleton fetuses, but there were no significant differences in the frequencies of the five other facial expressions between the fetal groups. Conclusion Our results suggest that restricted twin fetal behavior before 20 weeks of gestation may still affect the frequencies of twin facial expressions early in the third trimester of pregnancy. Moreover, the frequencies of facial expressions in twins are different from those of singleton fetuses.

Neurological development may be accelerated in growth-restricted fetuses: a 4D ultrasound study

Objective To assess whether neurological maturation and development are accelerated in fetal growth restriction (FGR) in utero using four-dimensional (4D) ultrasound. Methods The facial expressions of 50 appropriate-for-gestational-age (AGA) and 34 FGR fetuses aged between 28 and 35 gestational weeks were assessed using 4D ultrasound. Subsequently, they were differentiated into two gestational age groups (19 aged 28-31 weeks and 31 aged 32-35 weeks in AGA, and 15 aged 28-31 weeks and 19 aged 32-35 weeks in FGR). Fifteen-minute recordings were made, and the frequencies of seven facial expressions during that time were examined. Correlation analysis was conducted to assess the changing number of significant correlations with advancing gestation in each group. Results Out of 21 combinations of facial expressions at 28-31 and 32-35 gestational weeks in AGA fetuses, there was only three significant correlations. Similarly, only one was noted out of 21 combinations at 28-31 gestational weeks, but there were seven significant correlations in FGR fetuses at 32-35 weeks (P=0.018). However, there was no significant difference in the number of correlations of facial expressions between AGA (3/21) and FGR (7/21) fetuses at 32-35 weeks of gestation (P=0.147). Conclusion Our results suggest that the number of significant correlations of fetal facial expressions in FGR fetuses increases more compared with that in AGA fetuses at 32-35 weeks of gestation. Due to the acceleration of neurological maturation and development in FGR fetuses, the control of facial expressions by the brain may be more evident compared with AGA fetuses at 32-35 weeks of gestation. However, the data and their interpretation in the present study should be taken with some degree of caution because of the small number of subjects studied. Further studies involving a larger sample size are needed to obtain strong or additional evidence.