D1.169 - Monitoring of pulmonary function in pregnant women with severe asthma controlled in a monographic asthma and pregnancy unit

Pregnant women with severe asthma have a higher risk of worsening symptoms during pregnancy (52-65%) than those with mild or moderate asthma (8-13%).These data support the need for closer monitoring and appropriate treatment adjustments for pregnant women with asthma to achieve the best possible pregnancy control and a lower rate of complications for both mother and fetus. This analysis presents the monitoring of lung function and exhaled nitric oxide (FeNO) levels in this group of patients followed during pregnancy. 

From the total number of asthmatic patients followed at a specialized asthma during pregnancy clinic in a high-complexity unit, those with severe asthma diagnosed prior to conception were selected. Spirometry and FeNO measurement were performed at each visit during the three trimesters of pregnancy. Medication was adjusted at each visit according to established clinical and functional criteria, as per the GEMA 5.5 guidelines.

A statistical analysis was performed on the evolution of these parameters, measured by the Tiffeneau ratio, absolute and relative FEV1 values, and FeNO measured in ppb (parts per billion), at the three visits and before delivery.

A total of 40 pregnant women with severe asthma were analyzed, with the characteristics shown in Table 1. With asthma control, a statistically significant improvement in function and inflammation was observed (Table 2) from the first trimester visit (1T) with a mean FEV1/FVC of 66.4%, FEV1 of 63.4% (45-104), FeNO 23 (5-85), during the second trimester (2T) with FEV1/FVC values ​​of 69.7%, FEV1 of 71.5% (49-120), FeNO 15 (6-38) and the third trimester (3T) with FEV1/FVC 70.5%, FEV1 80% (54-112) and FeNO 10 (4-23). The Friedman test showed a statistically significant decrease (p=0.034) in FeNO values ​​as shown in Figure 1.

Close control of severe asthma in a specialized asthma management clinic during pregnancy improves lung function, measured by forced spirometry and pulmonary inflammation parameters in each trimester of pregnancy, reaching normal values ​​before delivery.