Heart volume and physical fitness of parturients.

One hundred and three primigravidae were studied to establish the correlation between physical fitness and heart volume. Twenty-three of the mothers were allocated at random to the exercise group and 21 to control group 1, between the 10th and 14th weeks of pregnancy. In addition, 59 mothers were allocated to control group 2, which was formed two weeks before term. The exercise group underwent a rather strenuous training programme during pregnancy. Physical fitness was measured by work tests on a bicycle ergometer two weeks before term. The heart volume was determined radiologically on the 6th day post partum. There was a positive correlation between physical fitness and the relative heart volume, which was greatest when physical fitness was measured by a method which takes the level of training into consideration. The relative heart volume of the exercise group was almost significantly greater than that of control group 1. The physical performance of the exercise group was very significantly greater than in the control groups. There was no significant correlation between either physical fitness or relative heart volume and the duration of pregnancy or the weight of newborn.