Infertility treatment associated with childhood asthma and atopy.

<bold>Study Question: </bold>Are children who were conceived with infertility treatment at an increased risk of developing asthma and atopic conditions?<bold>Summary Answer: </bold>Infertility treatment is associated with an elevated risk of asthma and atopic conditions in early and middle childhood, even after adjustment for parental asthma and atopy.<bold>What Is Known Already: </bold>Asthma and atopic conditions are prevalent in childhood. The development of these conditions may be linked to early life exposures, including the use of infertility treatments.<bold>Study Design, Size, Duration: </bold>Upstate KIDS is a prospective cohort study of singletons and multiples born between 2008 and 2010. A total of 5034 mothers and 6171 children were enrolled and followed up until 2019, and 2056 children participated in the middle childhood follow-up.<bold>Participants/materials, Setting, Methods: </bold>Women reported the fertility agents used to become pregnant on a baseline questionnaire. Treatment was categorized as ART (∼22%) use, ovulation induction via oral/injectable medications with or without IUI (OI/IUI, ∼20%), or no treatment (∼58%). Outcomes were assessed by maternal report on questionnaires in early (up to age 3 years, prevalence 9-28%) and middle (7-9 years, prevalence 10-16%) childhood. Weighted Poisson regression models with robust standard errors were used to analyze the risk of atopic outcomes in relation to infertility treatment exposure.<bold>Main Results and the Role Of Chance: </bold>Compared to children conceived without treatment, children conceived with any infertility treatment were at an increased risk of persistent wheeze by age 3 years (relative risk (RR): 1.66; 95% CI: 1.17, 2.33) with adjustments for parental atopy among other risk factors. Around 7-9 years, children conceived with treatment were more likely to have current asthma (RR: 1.30; 95% CI: 0.98, 1.71), eczema (RR: 1.77; 95% CI: 1.25, 2.49) or be prescribed allergy-related medications (RR: 1.45; 95% CI: 1.06, 1.99). Similar effect sizes were found when examining associations by treatment type (i.e. ART versus OI/IUI).<bold>Limitations, Reasons For Caution: </bold>Childhood outcomes were based on maternal report and are subject to potential misclassification. There was attrition in this study, which limits the precision of our measures of association.<bold>Wider Implications Of the Findings: </bold>Though future research is needed to clarify the mechanisms involved, our findings support that both ART and OI/IUI influences the development of asthma and atopic conditions in the offspring from an early age.<bold>Study Funding/competing Interest(s): </bold>This work was supported by the National Institutes of Health's Intramural Research Program at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD; contracts #HHSN275201200005C, #HHSN267200700019C, #HHSN275201400013C, #HHSN275201300026I/27500004, #HHSN275201300023I/27500017). The authors have no relevant conflicts of interest to disclose.<bold>Trial Registration Number: </bold>N/A. [ABSTRACT FROM AUTHOR]