Longitudinal study of peak expiratory flow rate in pregnant women.

ABSTRACT

Background: Several changes have been reported in the maternal pulmonary function tests during pregnancy. A longitudinal study was undertaken to document these changes throughout pregnancy using Peak Expiratory Flow Rate (PEFR). Effect of age and height on PEFR was also documented. Method:The study included 100 pregnant females and 100 non-pregnant female controls. PEFR was measured in each trimester of pregnancy at postpartum with Mini Wright peak flow meter and the highest value of PEFR from three correctly performed blows was considered. Results: There was a decrease in mean PEFR as the pregnancy advanced from 1st to 3rd trimester and increase in PEFR in post-partum, both being statistically significant. PEFR had significant negative correlation with age. Mean PEFR increased with an increase in age of the study subjects in all the 3 trimesters of pregnancy, with maximum value at 24 -29 years of age and there after started declining. PEFR had highly significant positive correlation with height in all the 3 trimesters of pregnancy. Conclusion: The study documented the changes in PEFR during pregnancy, the effect of age and height on PEFR along with their prediction equations.