- The effects of RO4929097 on the developing human fetus at the recommended therapeutic dose are unknown; Notch signal pathway inhibitors are known to cause interruption of the embryonic signaling pathway and may lead to serious or life-threatening birth defects, including brain deformities, facial malformation, heart problems, or abnormal organs; therefore, women of childbearing potential and men must use two forms of contraception (i.e., barrier contraception and one other method of contraception) at least 4 weeks prior to study entry, for the duration of study participation, and for at least 3 months post-treatment; should a woman become pregnant or suspect she is pregnant while she or her partner are participating in this study and for 3 months after study participation, the patient should inform the treating physician immediately