Human fetal breathing and gross body activity relative to maternal meals during insulin-dependent pregnancy.

Measurement of the percentage incidence of fetal breathing and gross body movements as well as of maternal blood glucose concentration was carried out in 12 insulin-dependent diabetic pregnant women and 12 normal controls between 33 and 37 weeks of gestation. The observation period was related to the three meal times. In diabetics no diurnal variation in pre-prandial fetal breathing activity was observed whereas in normal controls fetal breathing incidence was significantly higher before evening dinner than before breakfast. Immediately following lunch and dinner, fetal breathing demonstrated a significantly lower incidence in diabetics than in normals. Since no significant difference in maternal blood glucose concentration was found between the two groups, it is suggested that other factors relative to carbohydrate metabolism may also be involved in the regulation of fetal breathing in diabetes. Fetal gross body activity in diabetics vs. normals did not differ essentially and demonstrated no correlation with the maternal blood glucose levels.