Changes in pulmonary function during pregnancy: a longitudinal cohort study
Article first published online: 18 OCT 2011
© 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG
BJOG: An International Journal of Obstetrics & Gynaecology
Volume 119, Issue 1, pages 94–101, January 2012
How to Cite
Grindheim, G., Toska, K., Estensen, M.-E. and Rosseland, L. (2012), Changes in pulmonary function during pregnancy: a longitudinal cohort study. BJOG: An International Journal of Obstetrics & Gynaecology, 119: 94–101. doi: 10.1111/j.1471-0528.2011.03158.x
- Issue published online: 13 DEC 2011
- Article first published online: 18 OCT 2011
- Accepted 21 August 2011. Published Online 18 October 2011.
- Longitudinal study;
- lung function during pregnancy;
Please cite this paper as: Grindheim G, Toska K, Estensen M, Rosseland L. Changes in pulmonary function during pregnancy: a longitudinal cohort study. BJOG 2012;119:94–101.
Objective To record any physiological changes in lung function during healthy pregnancies, and evaluate the influence of parity, pregestational overweight, and excessive weight gain.
Design Longitudinal cohort study.
Setting Antenatal clinic at Oslo University Hospital.
Population One hundred healthy white women with singleton pregnancies.
Methods The women were studied with repeated measures of lung function using spirometry at a gestational age of 14–16, 22–24, 30–32, and 36 weeks, and at 6 months postpartum.
Main outcome measures Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and peak expiratory flow (PEF), also expressed as a percentage of predicted values according to age and height: i.e. FVC%, FEV1%, and PEF%.
Results Both FVC and FVC% increased significantly after 14–16 weeks of gestation (P = 0.001), as was the case for both PEF and PEF% (P < 0.001). FVC, FVC%, PEF, and PEF% in early and mid-pregnancy were significantly lower compared with the postpartum value (all P < 0.05). Nulliparous women had an overall 4.4% lower value of FVC% than parous women (P = 0.039). There were no differences in FVC, FEV1, or PEF dependent upon pregestational overweight or excessive weight gain.
Conclusions Forced vital capacity (FVC) increases significantly after 14–16 weeks of gestation. The FVC% is significantly higher in parous compared with primigravida women, suggesting that the changes in FVC occurring during pregnancy persist postpartum. PEF increases significantly during healthy pregnancies, and should be interpreted cautiously in pregnant women with impaired lung function.