The results of a clinical observation study show that asthma has been associated with a prolonged time to pregnancy and a decreased birth rate.
The current study investigated 245 women with unexplained fertility problems aged between 23 and 45 years. They underwent asthma and allergy testing and questionnaires during their fertility treatment. Ninety-six women in the study had either an existing doctor’s diagnosis of asthma or were diagnosed with asthma when they entered the study.
The researchers monitored the women during their fertility treatment for a minimum of 12 months, until they had a successful pregnancy, stopped treatment or the observation ended.
The results found that the median total time to pregnancy was 32.2 months in non-asthmatic women and 55.6 months in those with asthma. Women with asthma also had fewer successful conceptions: 39.6% achieved pregnancy in the asthmatic women compared with 60.4% in the women without asthma. The results also found this trend was more apparent as the women got older.
Lead author Dr Elisabeth Juul Gade, commented: “This finding in a clinical trial setting adds new weight to the epidemiological evidence suggesting a link between asthma and fertility. We have seen here that asthma seems to have a negative influence on fertility as it increases time to pregnancy and even more so with age.