II. Pathophysiology
- Teratogens cause birth defects, Stillbirths, IUGR
 
III. Risk Factors: General Teratogen Susceptibility
- Week 0-2: Pre-organogenesis
- Not Sensitive to malformation
 - Significant exposure is lethal
 
 - Week 3-8: Embryonic Period
- Greatest sensitivity to environmental exposures
 - Fetal mass increases 2.5 Million fold first trimester
 - Major malformations occur
 
 - Week 9-38: Fetal Period
- Decreasing sensitivity
 - Functional defects and minor malformations occur
 
 
IV. Causes: Occupational Exposures
- 
                          General
- Household products also present Teratogen Exposure risk (Heavy Metals, solvents, Pesticides)
 - High risk industries for Teratogen Exposure include laboratory work, dry cleaning, printing, manufacturing and agriculture
 
 - Lead Exposure
- Gestational Hypertension
 - Placenta Previa
 - Preterm delivery
 - Fetal loss
 - Fetal Growth Retardation
 - Fetal neurodevelopmental conditions
 - Birth defects
 
 - 
                          Mercury Exposure
- See Mercury Content in Fish
 - Preterm birth
 - Fetal neurodevelopmental conditions (potent Neurotoxin)
 
 - Solvents (Trichloroethylene, Chloroform, Benzene)
- Ensure adequate ventilation if at risk of exposure
 - Associated with risk of Miscarriage, Stillbirth, preterm birth and IUGR
 
 - Plastics (Vinyl Chloride)
 - Pollutants (Polychlorinated or Polybrominated Biphenyl)
 - Pesticides (Organophosphates)
 - Gases (Carbon Monoxide, Inhalation Anesthetics)
 - Radiation (e.g. XRay)
 
V. Causes: Home Exposures
- Medications
- See Medications in Pregnancy
 - Reevaluate all OTC and prescribed medications
 
 - Substances
- See Substance Abuse in Pregnancy
 - Tobacco Cessation
- Tobacco associated with 4600 U.S. perinatal deaths per year
 
 - Alcohol Abstention
 - Marijuana
- Associated with low birth weight and NICU admission
 - Heavy use is associated with Cannabinoid Hyperemesis and Preterm Labor
 - Avoid in pregnancy
 
 
 - Foods
- See Nutrition in Pregnancy
 - See Mercury Content in Fish
- Avoid excessive large fish intake (e.g. shark, swordfish, tilefish or king mackerel) due to mercurcy contamination
 
 
 - Vitamins
 - 
                          Herbals associated with Miscarriage
- Devil's claw root
 - Barberry
 - Dong Quai
 - High concentrations of Ruta, Hydrastis or Oregano
 
 - Other Herbal Teratogens
- See Herbal Remedy
- Exercise caution regarding overall risks of herbal contamination and lack of standardization
 
 - Ginkgo
 - Ephedra
 - Ginseng
 
 - See Herbal Remedy
 - Other home exposures
- Avoid hot tubs and saunas in first trimester
- Associated with Neural Tube Defects and Miscarriages
 
 - Avoid hair dyes and treatments in first trimester
- May be associated with childhood Acute Leukemia
 - Couto (2013) Chem Biol Interact 205(1): 46-52 [PubMed]
 
 
 - Avoid hot tubs and saunas in first trimester
 
VI. Resources
- CDC Medications in Pregnancy
 - Vaccines and Medications in Pregnancy Surveillance System (VAMPSS)
 - MotherToBaby Fact Sheets (from Organization of Teratology Information Specialists or OTIS)