Additional Study Information: Itacitinib is an investigational drug that is being developed by Incyte Corporation for use in the treatment of acute graft-versus-host disease (GVHD). At this time, it is not known whether the study drug has an effect on sperm or eggs, whether they are secreted in the semen or whether they have an effect on a fetus. We would like to collect medical information about you, your pregnancy, and the outcome of your pregnancy so that we can make a record of whether the study drug does or does not appear to have any effect.