Fetal movements in human pregnancies in the third trimester.

Fetal movements (FM) were measured using a real-time B-scan method in 50 women in the third trimester. One hundred ninety-five observations were made. The number of FM per 20-minute observation period was similar in normal, diabetic, and hypertensive pregnancies and in patients with placenta previa, but was significantly lower in patients with Rh isoimmunization and an affected fetus. The number of FM did not vary with gestational age, mode of delivery, or birth weight and was significantly increased in patients either with a reactive nonstress test (NST) or in the presence of fetal breathing movements (FBM). Fetal movements were absent before delivery in 4 patients: In 3, the fetus died in utero and in the other a positive contraction stress test (CST) was observed. Conversely, in 2 other fetuses who died in utero, FM were observed during the last examination before death. In both, the cause of fetal death was related to an acute change. No relationship between FM and neonatal death was observed. These data suggest FM monitoring may be helpful in evaluating antepartum fetal condition.