Overview Week 1-3 "all-or-none": the embryo either dies or survives without any complications Week 3-8 (embryonic period) most vulnerable time period due to organogenesis Week 8-38 growth and function of organ/embryo is affected decreased susceptibility due to organs already formed Teratogens Examples Effects on Fetus ACE inhibitors Renal damage renal dysplasia Alcohol Fetal Alcohol Syndrome (see below) Alkylating agents Absence of digits Cleft palate Renal agenesis Aminoglycosides CN VIII toxicity Anticonvulsants Cleft lip and palate Cocaine Abnormal fetal development Fetal addiction Low-birth weight Placental abruption Diethylstilbestrol (DES) Vaginal clear cell adenocarcinoma Other cervical, ovarian, and uterine abnormalities Folate antagonists Neural tube defects (REVIEW) myelomeningocele Lithium Ebstein's anomaly atrialized right ventricle Maternal diabetes Caudal regression syndrome sirenomelia renal dysplasia or aplasia imperforate anus Phenytoin Cleft lip and palate Congenital heart defects Potassium iodide Congenital goiter or hypothyroidism Cretinism Nicotine Premature delivery Low birth weight Intrauterine growth retardation ADHD Tetracyclines Discolored/stained teeth Thalidomide Gastrointestinal atresia Absence or malformation of external ear Phocomelia "seal" limbs Valproate Inhibits intestinal folate absorption leading to neural tube defects Cleft lip Renal defects Vitamin A/isotretinoin Spontaneous abortions Cleft palate Cardiac abormalities Eye and external abnormalities Warfarin Bone deformities femur, vertebral, and calcaneus show stippled appearance on X-ray Fetal hemorrhage Abortion Spasticity and seizures Fetal Alcohol Syndrome Fetal alcohol syndrome (FAS) pregnant mothers who consume alcohol increase their risk of delivering a child with FAS: mental retardation limb dislocation cardiovascular defects such as ventricular septal defects microcephaly holoprosencephaly facial abnormalities: hypertelorism, short palepebral fissures, long philtrum heart and lung fistulas alcohol is leading cause of mental retardation