Fetal motor activity in breech presentation.

Intrauterine motor activity was studied in breech presenting but otherwise normal fetuses. In the first part of the study, 48 fetuses were examined in the 33rd gestational week with an objective method using four piezo-electric crystals attached to the maternal abdomen for recording fetal movements. Of the 48 fetuses, 25 remained in breech presentation until delivery, while 23 assumed the vertex presentation before birth. In the second part of the study, 63 pregnant women with breech-presenting fetuses in the 33rd gestational week subjectively recorded perceptible movements every evening. Spontaneous cephalic version occurred in 40 cases, and 23 fetuses persisted in the breech presentation until delivery. Neither in the objective nor in the subjective study were any quantitative differences in motor activity found between fetuses subsequently born in breech presentation and these born in vertex presentation.