Table 1. Summary of cancer therapies and their effects on gestation.

	Early first trimester conception-4 weeks	First trimester 4 weeks-14 weeks	Second trimester 14 weeks-28 weeks	Third Trimester 28 weeks-delivery
Chemotherapy	All or none a	High risk of severe fetal malformation. Increased risk of miscarriage 3, 8, 16, 17	Growth restriction, low birth weight, preterm labor, myelosuppression, need for NICU admission 3, 8, 17	Growth restriction, low birth weight, preterm labor, myelosuppression, need for NICU admission 3, 8, 17
Anti-HER2 agents b	Fetus unaffected in review of limited case reports 18	Fetus unaffected in review of limited case reports 18	Oligohydramnios/ Anhydramnios 18	Oligohydramnios/ Anhydramnios 18
Hormonal therapy c	Possible increased risk of miscarriage 19	Facial malformations, ambiguous genitalia, possible increased risk of miscarriage, some cases with no adverse effects observed, data limited to animal studies and case reports 2, 19	Insufficient data 19	Insufficient data 19
Immunotherapies	Increased risk of miscarriage 3	Increased risk of miscarriage 3	Increased risk of stillbirth, premature delivery, infant mortality 3	Increased risk of stillbirth, premature delivery, infant mortality 3
Angiogenesis inhibitors	All or nonee	Increased risk of miscarriage, skeletal malformations, abnormal vascular development of the skin, pancreas, kidney, and lung 11	Intrauterine growth restriction, preeclampsia, hypertension 11	Intrauterine growth restriction, preeclampsia, hypertension 11
Radiation therapy d	All or none e	Gross malformation, small head size, mental retardation 20	Mental and growth retardation, small head size, cataracts, sterility, secondary malignancies 20	Growth retardation, sterility, cataracts, secondary malignancies 20
Surgery e	1–2% increased risk of miscarriage 8	1–2% increased risk of miscarriage 8	Premature delivery 8	Premature delivery 8

^aAn “all or none” effect means that the pregnancy either will fail or will continue without issue. ^bThese effects are derived largely from studies of trastuzumab. ^cEffects listed are those seen in studies evaluating tamoxifen use in pregnancy. ^dEffects seen at fetal exposures of more than 0.3 Gy ⁹. ^eRisks seen primarily in abdominal and pelvic surgery. NICU, neonatal intensive care unit. Illustrations by Katelyn Folsom.