Correlation between perinatal abnormalities and decreased fetal movement as counted by a fetal movement acceleration measurement recorder: A prospective cohort study.

Objective: The objective was to study the relationship between a decrease in gross fetal movement during maternal night sleep counted by an objective method and abnormal perinatal outcomes.

Methods: This was a prospective cohort study. A total of 470 pregnant women recorded fetal movement with the fetal movement acceleration measurement recorder weekly after 28 weeks. The ratio of 10-s epochs with fetal movement to all epochs was calculated as the fetal movement parameter. When the parameter was below the 10th percentile of the previously made reference curve, it was defined as decreased movement. Women who showed a decreased movement at least once were classified into a study group, and the other women were classified into a control group. Abnormal perinatal outcomes between the two groups were compared with the Chi-square test.

Results: There were more preterm births (19%) in the study group than in the control group (10%) (P = 0.0210). There was a significant difference for iatrogenic preterm birth (P = 0.0241) but not for spontaneous preterm birth (P = 0.4566). There were more hypertensive disorders of pregnancy (11.6%), small-for-gestational-age newborns (10.7%), and Apgar scores below 7 points at 1 min (7.4%) in the study group than in the control group (5.2%, 4.8%, and 2.6%, respectively) (P = 0.0329, 0.0459, and 0.0487, respectively).

Conclusion: A decrease in gross fetal movement during maternal night sleep was related to iatrogenic preterm births, small-for-gestational-age newborns, hypertensive disorders of pregnancy, and low Apgar scores at 1 min.