- Be willing to consistently take appropriate measures to avoid pregnancy through the Week 48 study point. All subjects will be informed of the potential risks of ustekinumab during pregnancy and counseled on pregnancy avoidance appropriate to the subject s circumstances (e.g. fertility status, medical contraindications to hormonal birth control, and/or personal or religious beliefs regarding pregnancy avoidance). Subject to the judgment and discretion of the PI, some subjects may not need to take pregnancy