Effects of Pregnancy-Onset Asthma on Perinatal Outcomes: A Retrospective Cohort Study

It is unknown whether women with pregnancy-onset asthma are predisposed to worse pregnancy outcomes compared with women with pre-pregnancy asthma.

To explore whether pregnancy-onset asthma leads to worse perinatal outcomes compared with pre-pregnancy asthma.

Women who were discharged with a diagnosis of asthma and gave birth to a live singleton were included in this retrospective cohort analysis. Women were separated into groups based on whether the asthma was diagnosed during or before pregnancy. We compared clinical characteristics, perinatal outcomes, and asthma exacerbations (AEs) between groups.

A total of 335 women were included in this study, 39 of whom (11.6%) had pregnancy-onset asthma and 296 had pre-pregnancy asthma. All pregnant women in the pregnancy-onset group experienced AEs during pregnancy. The proportion of chronic hypertension, chronic hypertension with superimposed preeclampsia, and spontaneous preterm births in the pregnancy-onset group was significantly higher than that in the pre-pregnancy asthma group. After adjusting for age, body mass index, onset of asthma during pregnancy, and severity of AEs through multivariate analysis, pregnancy-onset asthma was an independent risk factor for spontaneous preterm birth (adjusted odds ratio = 7.71; 95% CI, 1.30-46.12) and severe AE was an independent risk factor for gestational hypertension and preeclampsia (adjusted odds ratio = 3.58; 95% CI, 1.30-9.87).

During pregnancy, pregnancy-onset asthma in women is associated with an exacerbation of the condition. Obstetricians should be vigilant for signs of asthma onset during pregnancy. Other health care providers should watch for symptoms of gestational hypertension and preeclampsia in pregnant women with preexisting or new-onset asthma.