The management of asthma with short-acting beta-agonists (SABAs) was associated with reduced fertility rates in women, whereas treatment with inhaled corticosteroids (ICS) or long-acting beta-agonists (LABAs) was not, according to the results of the multicenter, prospective cohort Screening for Pregnancy Endpoints (SCOPE) study conducted in New Zealand, Australia, Ireland, and the United Kingdom, and published in the European Respiratory Journal.
Participants in the SCOPE study were healthy, nulliparous women who were recruited between November 2004 and February 2011. The primary objective of SCOPE was to develop screening tests for the prediction of preeclampsia, spontaneous preterm birth, and small-for-gestational-age neonates.
Asthma was self-reported and identified based on the question, “Have you been diagnosed with asthma by a doctor?” Women with asthma were further divided according to symptoms and asthma medication use, being classified as having either former asthma (defined as physician-diagnosed asthma, with the woman experiencing no symptoms in the past 12 months and no current use of asthma medications) or current asthma (defined as physician-diagnosed asthma, with the woman experiencing asthma symptoms in the past 12 months and/or use of asthma reliever or preventer medications).
Women with current asthma were further divided based on the use of intermittent reliever medications only (ie, SABAs) or additional use of reliever medications (ie, ICS with or without LABAs). Thus, there were 3 subgroups of women with asthma: former asthma, SABA users, and ICS±LABA users.
Information was compiled on participants’ demographics, smoking status, family/medical/gynecologic history, and height/weight. Self-reported time to pregnancy, which was defined as the duration of sex (in months) without contraception before the current pregnancy, was reported in the first trimester. Subfertility denoted time to pregnancy >12 months. Fecundability odds ratios (FORs) were used to estimate the odds of conceiving in each cycle, given exposure to asthma and dependent on not being pregnant in the previous cycle.
In a total of 5617 women enrolled in the study, 19.7% reported physician-diagnosed asthma. Of the women with asthma, 11.7% currently had asthma and 8.0% formerly had asthma. Women with either current or former asthma were younger, had a higher body mass index, were more likely to smoke, to be white, and have a lower socioeconomic status, compared with women who did not have asthma.
Moreover, compared with women without asthma, women with current asthma who were managed with SABAs had adjusted FORs that were 15% lower (FOR, 0.85; 95% CI, 0.75-0.96), whereas there was no difference observed in women with former asthma (FOR, 1.00; 95% CI, 0.89-1.13) or women with current asthma using ICS±LABA (FOR, 0.98; 95% CI, 0.84-1.15). In addition, compared with women without asthma, point estimates for nonfertility were increased in SABA users (adjusted OR [aOR], 1.30; 95% CI, 0.93-1.81), but not in women with former asthma (aOR, 0.89; 95% CI, 0.62-1.28) or among current ICS±LABA users (aOR, 1.08; 95% CI, 0.69-1.71).
The investigators concluded that asthma is associated with reduced fertility, with the greatest effect experienced by women with current asthma who receive intermittent SABA therapy. Women who have asthma and are planning to become pregnant should be encouraged to continue taking their preventer medications.
Grzeskowiak LE, Smithers LG, Grieger JA, et al. Asthma treatment impacts time to pregnancy: evidence from the international SCOPE study. Eur Respir J. 2018;51(2).