A longitudinal study of antenatal changes in lung function tests and importance of postpartum exercises in their recovery.

A study of changes in lung function tests during pregnancy was undertaken in fifty pregnant women beginning from third month of gestation. Fifty nonpregnant age and height matched women formed the controls. Forced Vital Capacity (FVC), Timed Vital Capacity (FEV1), Inspiratory Capacity (IC), Expiratory Reserve Volume (ERV) and peak Expiratory Flow Rate (PEFR) were performed in each month of pregnancy. However ten subjects were not available for follow-up during postpartum period. Remaining forty women were divided into two groups of twenty each. Group I performed daily graded active exercises to strengthen the anterior abdominal wall muscles. Group II women did not perform any exercises. It was observed that the antenatal changes in percent FVC and FEV1 were insignificant, but the decline in ERV and PEFR were very highly significant (P < 0.001) and the increment in IC was significant (P < 0.05). In the postpartum period the percentage variation of values in group I was less than 5% from controls (P > 0.05) and in group II it was 15-20% from controls (P < 0.05), resulting in a significant variation in group II women as compared to the controls. It is concluded that there are adaptive changes in lung functions in the antenatal period. We stress the importance of regular graded active exercises in the postpartum period for the speedy recovery of these changes.