Coexistence of infertility and asthma has been observed clinically. Therefore, we investigated the association between asthma and delayed pregnancy in a nationwide population-based cohort of twins.A cohort of 15 250 twins living in Denmark (aged 12-41 years) participated in a questionnaire study including questions about the presence of asthma and fertility. Differences in time to pregnancy and pregnancy outcome were analysed in subjects with asthma, allergy and in healthy individuals using multiple regression analysis.Asthma was associated with an increased time to pregnancy, the percentage of asthmatics with a time to pregnancy .1 year was 27% versus 21.6% for non-asthmatics (OR (95% CI) 1.31 (1.1-1.6); p50.009). The association remained significant after adjustment for age, age at menarche, body mass index and socioeconomic status (OR (95% CI) 1.25 (1.0-1.6); p50.05), and was more pronounced in those .30 years of age (32.2% versus 24.9%, OR (95% CI) 1.44 (1.1-1.9); p50.04). Untreated asthmatics had a significant increased risk of prolonged time to pregnancy compared to healthy individuals (OR (95% CI) 1.79 (1.20-2.66); p50.004), while asthmatics receiving any kind of treatment for asthma tended to have a shorter time to pregnancy than untreated asthmatics (OR 1.40; p50.134).Asthma prolongs time to pregnancy. The negative effect of asthma on fertility increases with age and with disease intensity, indicating that a systemic disease characterised by systemic inflammation also can involve reproductive processes. @ERSpublications Asthma prolongs time to pregnancy: the negative effect of asthma on fertility increases with age and disease intensity

Early menarche appears to be associated with increased risk of asthma. Hormonal, immunological, genetic and environmental factors may act in a developmental context to explain this relationship. Future studies are warranted to further determine the mechanisms responsible for this observation.

Alcohol intake is associated with new-onset asthma in adults with a U-shaped association between amount of alcohol intake and the risk of asthma.

The pathogenesis of mastocytosis is not well defined and thus treatment remains challenging and remains on a palliative basis. We present two cases (a 48-year-old woman and a 57-year-old man) with indolent systemic mastocytosis in whom omalizumab (anti-IgE) reduced gastrointestinal and cutaneous symptoms significantly. This observation provides additional insight into the effects of omalizumab on systemic mastocytosis.

Early menarche is associated with increased risk of asthma among Danish female twins independently of BMI, age, physical activity, educational level and smoking. Results indicate a complex relationship possibly mediated through innate and non-genetic effects.