Women with inflammatory bowel disease (IBD) have similar rates of fertility to the general population, but have an increased rate of adverse pregnancy outcomes compared with the general population, which may be worsened by disease activity. Infertility is increased in those undergoing ileal pouch-anal anastomosis. Anti-tumor necrosis factor therapy in pregnancy is considered to be low risk and compatible with use during conception in men and women and during pregnancy in at least the first two trimesters. Infliximab (IFX) and certolizumab pegol are also compatible with breastfeeding, but safety data for adalimumab (ADA) are awaited. The safety of natalizumab during pregnancy is unknown. For children with Crohn's disease (CD), IFX is effective at inducing and maintaining remission. Episodic therapy is not as effective as scheduled infusions. Disease duration in children does not appear to affect the efficacy of IFX. IFX promotes growth in prepubertal and early pubertal Crohn's patients. It is also effective for the treatment of extraintestinal manifestations. ADA is effective for children with active CD and for maintaining remission, even if they have lost response to IFX, although there are fewer data. Vaccination of infants exposed to biological therapy in utero should be given at standard schedules during the first 6 months of life, except for live-virus vaccines such as rotavirus. Inactivated vaccines may be safely administered to children with IBD, even when immunocompromised.