Assignment on Teratogens

Teratogens are exogenous agents, such as certain chemicals, drugs, or viruses, that disrupt the normal processes of development.  For this assignment you will choose a teratogen, which is known to cross the placental barrier, and cause damage or long-lasting adverse effects to the developing embryo or fetus.  You will do some research on the teratogen and then answer questions below.

Here are some examples of teratogens which cross the placental barrier:

Class of Teratogen Some Potential Choices*
Recreational Drugs Alcohol, Cocaine, Methamphetamine, Nicotine
Infectious Agents Toxoplasma Gondii, Rubella, Cytomegalovirus, Varicella Zoster Virus (chicken pox), Treponema pallidum (Syphilis), Herpes Simplex viruses, Zika virus, others
Prescription Drugs Retinoic Acid (Accutane), Anti-convulsants, Others
Environmental contaminants Mercury, Lead, Others

 

*Before you get too attached to a specific teratogen, be sure that there is sufficient literature on the effects of the teratogen.  To answer question 1, there have to be epidemiological studies that demonstrate an association between exposure of pregnant women to the teratogen and adverse outcomes in their children.  To answer question 2 on the underlying biological mechanisms, there should also be animal studies on the effects of the teratogen.  For example, I do not recommend choosing thalidomide since this was a drug mostly prescribed in Europe (Germany) in the 1940s, thus there would be few epidemiological studies and they would be fairly old and mostly in German.

You must do some research on your teratogen choice in order to answer the following questions.  Here are the parameters for the types of resources you are required to use.  You must actually cite these resources in your answers to the questions below using in-text citations and include them in your reference list at the end. citations should follow APA format:

  • At least 1 review article from published peer-reviewed literature. For example, the following is a review article published in the Journal Nature Reviews Neuroscience on the effects of prenatal exposure to drugs:

Thompson, B. L., Levitt, P., & Stanwood, G. D. (2009). Prenatal exposure to drugs: effects on brain development and implications for policy and education. Nature Reviews Neuroscience, 10(4), 303.  doi: 10.1038/nrn2598

  • At least 1 primary research article from published peer-reviewed literature: For example, you could find an article that is an epidemiological cohort study which measured the relative risk of infants being born with birth defects or having a developmental delay when the mother was using a specific prescription drug during her pregnancy. You could also find an experimental study that looks at the biological mechanisms for the effects of the teratogen using animals.  The references at the end of your review article (or on some websites) are a good starting point for finding primary research articles.
  • At least 1 Reputable Website (such as government websites (.gov), The Teratology Society, hospital websites, charitable organizations, etc.)
  • Charitable organizations that support Child and Maternal Health, such as the March of Dimes.

https://www.marchofdimes.org/complications/pregnancy-complications.aspx

 

  • You may also cite chapters in books if you wish. For example, the Teratology Primer (https://birthdefectsresearch.org/primer/) has chapters on teratogens such as Alcohol, Prescription drugs like Anti-depressant medications, Environmental Toxins, and Infectious Diseases.

 

You MUST answer the following questions in your own words.  Do NOT quote directly from your sources.  You must paraphrase instead.

  • If you copy from sources, you have committed plagiarism. Turn-it-in software will be used to detect plagiarism.
  • You must cite every new idea you discuss that is not your own (e.g. that came from other sources or is not general knowledge) using in-text citations and include a list of references at the end (in APA format).
  • You must submit a Word document (not pdf) with a title page and your answers to the questions to the LEARN Dropbox for Assignment 2
  • Do not include the actual questions in your Word document, just the question number and subpart (i.e. 1b, 2a, etc).
  • Use a title page for your Assignment with the following:
    • HLTH/KIN/GERON310 Assignment 2 – Winter 2020
    • Title that includes name of Teratogen
    • Your name and Student ID number
  • Use 1.0 spacing and 10 pt Times New Roman Font.

Questions to Answer

1) Epidemiology of the teratogen and risks to development. Vulnerable populations.

1-a) Discuss a specific epidemiological study which measured the association between pregnant women’s exposure to the teratogen and adverse effects on the offspring (don’t forget to cite the study). What type of study was it, how was the study carried out (e.g. describe study design and methods), and what were the main results of the study?  Report on specific statistics to help indicate the risk, such as the odds ratio or relative risk, or prevalence of adverse outcomes in the offspring that were exposed in utero.  You may have to give different statistics for different types of deficits associated with the same teratogen. (18-20 sentences)

Rubric: (5 points)              

Excellent and thorough description of an epidemiological study that measured association between teratogen exposure and adverse effects in the offspring. Your description clearly included the following:

–  thoroughly described study design and methods, including: the type of epidemiological study design; characteristics of the recruited participants, inclusion and exclusion criteria; description of what was measured and at what time points

– Thoroughly described the main results of the study.

– You included statistics to indicate the risk of deficits with exposure to the teratogen. (at least two different statistics to be Excellent)

– You cited the study and/or other relevant sources throughout in your description.

1-b. Which particular populations of pregnant women or regions of the world are most vulnerable or have higher prevalence of exposure to this teratogen?  Explain and cite your sources. (9-10 sentences)

Rubric: (2 points)

– Excellent description of particular populations or regions of the world with higher prevalence of exposure to the teratogen.  Must describe at least 2 vulnerable populations or regions to be excellent.

-You cited relevant sources.

2 Biological aspects of the teratogen effects:

2-a Describe the congenital defects, disorders, or neurobehavioral deficits associated with prenatal exposure to the teratogen.  What organs or tissues are mostly affected?  What are the most sensitive periods of prenatal development for the types of defects described above? (9-10 sentences)

Rubric: (3 points)

Excellent description that includes:

  1. a) Thorough description of the congenital defects, disorders, and/or neurobehavioral deficits.
  2. b) organs and organ systems most affected
  3. c) the most sensitive periods of prenatal development for exposure to the teratogen (note that the sensitive periods may differ for different defects/outcomes)

– You also cited relevant sources.

2-b. For one of the defects described above, describe a potential underlying biological mechanism for the teratogenic effects during development (usually these data come from animal studies).  Be specific in your description of the biological mechanism (e.g. death of cells in a certain part of the brain leading to severe mental retardation, decrease in nutrient transport across the placenta leading to very low birth weight).  (5-6 sentences)

Rubric: (2 points)

Excellent description of a potential underlying biological mechanism for one of the defects/disorders/deficits that is specific and cites a relevant source (such as an animal study).

3) Take on the role of a public health educator.  You need to get the word out to the public on the potential harmful effects of this teratogen.  Come up with a strategy to disseminate the information (public service announcement on TV? infographic signs in certain places?).  In your strategy, discuss how you will target those who are more likely to be exposed to the teratogen or the most vulnerable segments of society (i.e. from part 1b).  What are the most salient points to make about the harmful effects of the teratogen, based on your answers to the above questions?  Keep in mind that you can’t be too technical in your wording or you will confuse or lose the interest of your audience.  Be creative and describe your strategy in at least 13 sentences (but no longer than 15 sentences).

Rubric: (4 points)

Uses excellent strategy to disseminate information to the public that is thorough, clear, and logical.

Strategy efficiently targets the people most likely to be exposed or most vulnerable populations/regions (eg focus on 1 of the regions or populations discussed in Q1b).

Emphasizes the most salient points on the harmful effects of the teratogen

Presents information in an engaging and simplified manner to hold the attention of the public.

Research, references, and citations (be sure to use proper APA format).

Rubric: (3 points)

Excellent use of sources, citations, and proper formatting of references.

Used the three required types of sources (Review article, primary research article, and reputable website).

Cited sources extensively where appropriate in the answers to the questions.

Provided a complete list of references at the end with proper APA formatting.