Snapshot A 35-year-old G1P0 woman gives birth to a baby with the scalp finding seen in the image. A few months prior to her discovery that she was pregnant, she had symptoms of palpitations, heat intolerance, and weight loss. She was diagnosed with Graves disease and prescribed methimazole by her endocrinologist. During her pregnancy, she missed several routine prenatal appointments and inadvertently continued taking many of the same medications that she had been taking prior to her pregnancy, including methimazole. Introduction Overview teratogens are agents that can cause abnormal fetal development and birth defects effects vary depending on timing of fetal exposure to the teratogen weeks 1-3 of gestation "all-or-none" effects the embryo either dies or survives without any complications weeks 3-8 of gestation embryonic period most susceptible time period due to organogenesis week 8 of gestation until birth growth and function of organs are affected Substance Abuse Teratogen Effects on Fetus Alcohol Fetal alcohol syndrome Cocain Low birth weight Preterm birth Intrauterine growth restriction Placental abruption Nicotine Low birth weight Preterm labor Placental problems Sudden infant death syndrome ADHD Medications ACE inhibitors (i.e., lisinopril) Renal damage renal dysplasia Alkylating agents (i.e., cyclophosphamide) Absence of digits Cleft palate Renal agenesis Aminoglycosides (i.e., gentamicin) Ototoxicity Antiepileptic drugs (i.e., phenytoin) Neural tube defects Cardiac defects Cleft lip and palate Diethylstilbestrol Vaginal clear cell adenocarcinoma Congenital cervical, ovarian, and uterine abnormalities Folate antagonists (i.e., methotrexate) Neural tube defects meningomyelocele Isotretinoin Multiple severe birth defects (i.e., cleft palate, microphthalmia, and congenital heart defects) Lithium Ebstein anomaly Methimazole Aplasia cutis congenita Tetracyclines (i.e., doxycycline) Discolored teeth Inhibited bone growth Thalidomide Limb defects Warfarin Bone deformities Fetal hemorrhage Abortion Opthalmologic abnormalities