The 5 complications most frequently reported in the anti-ERBB2 drug group were oligohydramnios (78 [23.8%]), preterm birth (57 [17.4%]), intrauterine growth restriction (32 [9.8%]), neonatal respiratory disorder (24 [7.3%]), and spontaneous abortion 24 [7.3%]). The gene discussed is ERBB2; the disease is fetal growth restriction.