The impacts of parity on lung function data : A comparative study

Background Studies evaluating the impacts of parity on LFD of healthy females presented controversial conclusions. Aim To compare the LFD of healthy females broken down according to their parities. Methods A medical questionnaire was administered and anthropometric data were determined. Two groups [G.sub.1 (n = 34): [less than or equal to] 6; G.sub.2 (n = 32): > 6] and three classes [C.sub.1 (n = 15): 1-4; C.sub.2 (n = 28): 5-8; C.sub.3 (n = 23): 9-14] of parities were identified. LFD (plethysmography, specific airway resistance (sRaw)] were determined. Student's t-test and ANOVA test with post-Hoc test were used to compare the two groups' and the three classes' data. Results G.sub.1 and G.sub.2 were age and height matched; however, compared to G.sub.1, G.sub.2 had a lower body mass index (BMI). C.sub.1, C.sub.2 and C.sub.3 were height, weight and BMI matched; however, compared to C.sub.2, C.sub.3 was older. G.sub.1 and G.sub.2 had similar values of FEV.sub.1, forced- and slow- vital capacities (FVC, SVC), maximal mid-expiratory flow (MMEF), forced expiratory flow at x% of FVC (FEF.sub.x% ), peak expiratory flow (PEF), expiratory and inspiratory reserve volumes (ERV, IRV, respectively), inspiratory capacity (IC), sRaw, FEV.sub.1 /FVC, FEV.sub.1 /SVC, and residual volume/total lung capacity (RV/TLC). The three classes had similar values of MMEF, FEF.sub.x%, PEF, thoracic gas volume (TGV), ERV, IRV, FEV.sub.1 /FVC, FEV.sub.1 /SVC and RV/TLC. Compared to G.sub.1, G.sub.2 had higher TGV (2.68±0.43 vs. 3.00±0.47 L), RV (1.80±0.29 vs. 2.04±0.33 L) and TLC (4.77±0.62 vs. 5.11±0.67 L). Compared to C.sub.1, C.sub.2 had higher FEV.sub.1 (2.14±0.56 vs. 2.47±0.33 L), FVC (2.72±0.65 vs. 3.19±0.41 L), SVC (2.74±0.61 vs. 3.24±0.41 L), TLC (4.47±0.59 vs. 5.10±0.58 L), IC (1.92±0.41 vs. 2.34±0.39 L) and sRaw (4.70±1.32 vs. 5.75±1.18 kPa*s). Compared to C.sub.1, C.sub.3 had higher TLC (4.47±0.59 vs. 5.05±0.68 L) and RV (1.75±0.29 vs. 2.04±0.30 L). Conclusion Increasing parity induced a tendency towards lung-hyperinflation.