Maternal perception of fetal movements in late pregnancy is affected by type and duration of fetal movement

Objective: A reduction in fetal movements has been proposed to identify pregnancies at risk of stillbirth. The utility of this approach is limited by variability in maternal perception of fetal movements. We aimed to determine the proportion of fetal movements observed by ultrasound that were maternally perceived and identify factors that affected maternal perception. Method: During 30-min recordings, women (n = 21) depressed a trigger upon perception of a fetal movement, while an ultrasound operator recorded observed movements according to the fetal parts involved. Results: Women perceived between 2.4% and 81.0% (median 44.8%) of movements observed on scan. Synchronous movement of the fetal trunk and limbs was more likely to be recognized than either part in isolation (60.5% versus 37.5% and 30%, respectively). The ultrasound operator judged the fetus to be moving for a significantly greater proportion of the time than mothers (median 1.5% of total recording time versus 0.7%). There was no significant relationship between the ability to perceive fetal activity and placental site, parity, amniotic fluid index or maternal body mass index. Conclusion: Variations in maternal perception of fetal movements may affect detection of a clinically significant reduction in fetal movements for some women.