Fetal general movements and brain sonography in a population at risk for preterm birth

Background

General movements (GMs) assessed three months post term are related to brain injury and neurological outcome.

Aims

To study GMs in fetuses and their predictive value for echogenicity changes in the fetal brain.

Study design

Prospective study of fetal GMs (classified as normal or abnormal) and echogenicity changes in the periventricular, basal ganglia/thalami area, and ventricular system (classified as absent, mild or moderate).

Subjects

121 fetuses from pregnancies affected by hypertensive disorders and/or preterm labour, at risk for preterm birth (26-34 weeks gestational age).

Outcome measures

Prevalence of abnormal GMs, GM parameters (amplitude, speed and complexity), and moderate echogenicity changes in the fetal brain (periventricular ≥ IB, intraventricular grade II/III, and basal ganglia/thalamus locally increased). Predictive values of GMs for clinical parameters and moderate echogenicity changes.

Results

GMs were abnormal in 58%, with amplitude affected in 96%, and speed and complexity in 59%. Abnormal GMs correlated with oligohydramnios (p = 0.002) and hypertensive disorders (p = 0.015). Echogenicity changes of the brain were absent, mild and moderate in 27%, 39% and 31%, respectively. The sensitivity of GMs for moderate echogenicity changes in the three areas combined was 0.65, and the periventricular area 0.85, specificity both 0.44, negative predictive values 0.73 and 0.96 respectively.

Conclusions

Qualitative abnormal GMs are frequent in fetuses of compromised pregnancies, and correlate with hypertensive disorders and oligohydramnios. The amplitude of GMs was most frequently affected. Abnormal GMs relate to moderate echogenicity changes especially in the periventricular area of the fetal brain, while normal GMs predict absence of moderate echogenicity changes.