Herceptin is not recommended due to an increased risk of oligo/anhydramnios. A reduced production of amniotic fluid is provoked by an effect on renal epithelium in which HER2/neu is strongly expressed. Also, an inhibition is observed of the VEGF, which regulates production and reabsorption of the amniotic fluid.
Tamoxifen is not recommended due to birth defects and syndromes. These include the Goldenhar syndrome, ambiguous genitalia and the Pierre Robin sequence.
Imatinib is used in Chronic Myeloid Leukemia (CML) and its effects during pregnancy are described by Pye and collegues. They report on 12/125 pregnancies with fetal abnormalities. Three of these were striking similarities: complex abnormalities with comparable aspects to effects observed in rodent studies
Imatinib should be used with caution during pregnancy, balancing the risk to the fetus versus the risk to the mother. Other options for CML during pregnancy include termination of pregnancy, close monitoring or interferon-alfa.