Objective Antitumour necrosis factor (TNF) during pregnancy in patients with IBD is related to high fetal anti-TNF levels. We evaluated maternal and child safety on discontinuing anti-TNF in the second trimester of pregnancy.

Design Two groups of women with IBD were prospectively followed-up during pregnancy: women in sustained remission stopped anti-TNF before week 25 (stop group) and the remaining group continued anti-TNF beyond week 30 (continue group). Maternal, birth and 1-year child outcomes were compared with children of non-IBD women.

Results Overall, 106 patients with 83 completed pregnancies were included. Relapse rate after week 22 did not differ between the stop (n=51) and continue (n=32) groups (5 (9.8%) versus 5 (15.6%), p=0.14). There was no difference in allergic reactions (p=1.00) or loss of response (p=1.00) postpartum between the two groups. Birth outcomes were comparable. Infants from both groups had lower birth weight (p=0.001), shorter gestational term (p=0.0001), were more often delivered via caesarean section (p=0.0001) and were less often breastfed (p=0.0001) compared with infants from non-IBD controls. Growth, infection rate, allergies, eczema and adverse reactions to vaccines were comparable across the stop and the continue groups as well as the children of anti-TNF-exposed and non-IBD women at 1 year.

Conclusions To limit anti-TNF exposure in utero, anti-TNF can be stopped safely in the second trimester in women with IBD in sustained remission. In patients not in sustained remission, anti-TNF may be continued without clear additional risks to the fetus. We observed excellent 1-year child outcomes compared with children from non-IBD controls.