EFFECT OF GESTATIONAL AGE AND SOME BIOPHYSICAL PARAMETERS ON VENTILATORY (PULMONARY) FUNCTION TEST IN NORMAL PREGNANT WOMEN
Background: The physiological nature of pregnancy entails substantial alteration in some physiological parameters. There is a dearth of published data concerning the
changes in ventilatory function during pregnancy in Nigeria and indeed Africa. Prior knowledge will help tremendously in the management of healthy pregnant women and those with respiratory disorders. Aim and Objectives. To establish some ventilatory function indices in healthy pregnant women in Enugu, South East Nigeria and to determine the effect of gestational age and biophysical parameters on some respiratory function values in normal pregnant women. Subjects and Methods; The work was undertaken in a cross-section of expectant mothers at the antenatal and booking clinics of the one tertiary, one secondary and one primary health care facility in Enugu. A total of 330 participants (250 healthy pregnant and 80 non-pregnant women) were enrolled in the study. Ventilatory functions were determined using a standard Spirometer. Results; The mean FVC, FEV1 and ERV in liters decreased significantly as the pregnancy progressed (P<0.001). However, the average TV(l) and FEV1/FVC (%) increased significantly (P=0.02, P < 0.001 respectively). Significant negative correlation occurred between the GA and FVC (P=0.001), FEV1 (P=0.01), ERV (P<0.001) and a significant positive correlation with TV (P=0.01) and, FEV1/FVC (P=0.02). The gestational age was a significant predictor for ERV, (P=0.02). Maternal age was a significant predictor for FVC (P<0.001), FEV1 (P<0.001) FEV1/FVC (P=0.02), and TV (P=0.05). Maternal height was a significant predictor for FVC (P=0.04) and, FEV1/FVC (P<0.01), the maternal weight was a significant predictor for TV (P=0.04) and ERV (P<0.01) and the BMI significantly
predicted the values of the ERV (P<0.01).Conclusion: Pregnancy induces physiological lung restriction. Maternal age predicted the values of all the parameters except ERV. The gestational age only predicted the values of ERV.