Asthma in 9-year-old children of subfertile couples is not associated with in vitro fertilization procedures

Asthma is a chronic reversible obstructive airway disease, which is common among children and leads to respiratory impairment. Studies showed that asthma is more common among children born after in vitro fertilization (IVF) than among spontaneously conceived children. However, it is unknown which component of the IVF procedure contributes to this putative link. Therefore, the aim of this prospective follow-up study was to differentiate the possible effect of ovarian hyperstimulation from that of the in vitro culture procedure on asthma and rhinitis in 9-year-old children conceived with IVF. The study comprised three groups of singletons: (I) conceived with ovarian hyperstimulation-IVF (COH-IVF, n = 95); (II) conceived with modified natural cycle-IVF (MNC-IVF, n = 48); and (III) naturally conceived to subfertile couples (Sub-NC, n = 68). Parents filled out the validated Dutch version of the asthma questionnaire of the International Study of Asthma and Allergies. Asthma prevalence in the groups did not differ: COH-IVF n = 8 (8%); MNC-IVF n = 0 (0%); and Sub-NC n = 4 (6%). Adjustment for confounders did not alter the results. Conclusion: Neither ovarian hyperstimulation nor the in vitro culture procedure was associated with asthma and rhinitis at 9 years. IVF children had a similar prevalence of asthma compared with children conceived naturally by subfertile couples. Trial registration: ISRCTN76355836 ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00431-019-03436-2) contains supplementary material, which is available to authorized users.