Short-acting asthma relievers have been linked to reduced fertility in women… but there’s good news for those who use long-acting preventers
Women with asthma who use short-acting asthma relievers may take longer to become pregnant than other women, according to a new study led by the University of Adelaide.
In the multicentre cohort study across Australia, New Zealand, the United Kingdom and Ireland, researchers looked at data for more than 5600 women expecting their first babies.
Nearly 20% reported diagnosed asthma and, of these, 11.7% were current asthmatics and 8% were former asthmatics.
Researchers found that women who had asthma, overall, took longer to get pregnant.
When the groups were separated according to the types of asthma medication the women were using, the researchers found no difference in fertility between women using long-acting asthma treatments and women without asthma.
Meanwhile, women using short-acting reliever medication (beta-agonists) took 20% longer to conceive on average.
They were also 30% more likely to have taken more than a year to conceive, which the researchers defined as the threshold for subfertility.
This difference remained after adjusting for confounders such as the woman’s weight and age.
“Several studies have identified a link between asthma and female infertility, but the impact of asthma treatments on fertility has been unclear,” says lead author Dr Luke Grzeskowiak on the results, which were published in the European Respiratory Journal.
Inflammation could be the link between asthma and reduced fertility in women, the researchers suggest.
“While the exact mechanisms underpinning our observations remain unclear, it has been hypothesised that asthma reduces uterine blood supply or increase infiltration of inflammatory cells into the decidua (the uterine mucosal layer), which impairs implantation.”
The results indicate that preventer medications may actually play a protective role in improving asthma control and reducing associated systemic inflammation, say the researchers.
“There is plenty of evidence that maternal asthma has a negative impact on the health of pregnant mothers and their babies, and so our general advice is that women should take steps to get their asthma under control before trying to conceive,” says Dr Grzeskowiak.
The researchers point out that the findings were not adjusted for socioeconomic status, presence of polycystic ovary syndrome, or age and BMI of the father, which could potentially influence the results.