P734 Anti-TNFa exposure during pregnancy is not associated with increased infection risk in exposed children during the first year of life

Abstract Background There has already been a solid evidence on safety of anti-TNFa therapy on foetal development and newborn outcome. However, there is still a lack of data on impact of the treatment on long-term evolution of the exposed children. Our aim was to assess the impact of in utero exposure to anti-TNFa due to mothers’ inflammatory bowel disease (IBD) on infectious risk during the first year of life of exposed children. Methods We prospectively included consecutive children (≥12 months of age) born to mothers with IBD (2007–2016) treated with anti-TNFa during pregnancy in three medical centres in Czech Republic. A control group of unexposed children born to non-IBD mothers undergoing regular mandatory check-up at general paediatricians was included and intended to be matched 1:1 by year of birth. Data (in both exposed children and controls) on birth, perinatal period, psychomotor development, vaccination, infections, antibiotic use and atopy were collected by treating paediatricians from children’s medical files using a predefined questionnaire and children′s vaccination cards. Only infections requiring antibiotics and/or hospitalisation were registered. Results Sixty-nine exposed and 42 unexposed children were included (median age 35 and 48 months at last follow-up, respectively). There was no significant difference in proportion of prematurity, low-birth weight, perinatal complications or smoking mothers comparing exposed ones and controls (p > 0.05). However, there was a trend to higher rate of nursing (≥4 months) in controls compared with exposed children (78.6% vs. 50.7%, p = 0.054). Infectious complications occurred in 23.2% of exposed and 19% of control children within their first year of life (p = 0.61). The type of infections were similar between the groups with the majority of them being respiratory. One child exposed to anti-TNFa experienced pseudomonas otitis media as a complication of surgery for cleft palate, otherwise no other opportunistic infection was observed. 26 (38.2%) IBD women obtained concomitant thiopurines during pregnancy with no difference in infections risk in exposed children (73.1% vs. 78.6%, p = 0.60). Cord levels of anti-TNFa were measured in 43 (62.3%) children and no impact of therapeutic (≥3 µg/ml) vs. non-therapeutic levels on infections rate was found (77.8% vs. 75%, p = 0.84). Conclusions Children exposed to anti-TNFa therapy due to maternal IBD seem to have similar risk of infectious complications during th