Abnormal Development - Thalidomide

Introduction

How and why do things go wrong in development?

Some Recent Findings

Australian Birth Anomalies System

"The national collation and reporting of birth anomalies data has been suspended in recent years due to concerns about data quality and comparability."

Variability among states and territories in scope of birth anomalies data collections
- sources of birth anomalies notifications
- definitions and classifications used
- method of data collection
- available resources
Variability among the states and territories in the timing and method of the provision of birth anomalies data to the AIHW National Perinatal Statistics Unit (NPSU) for national collation and reporting.
New Australian Birth Anomalies System should be data for birth anomalies detected up to 1 year of age
- including data on terminations of pregnancies with birth anomalies
- regardless of gestational age (i.e. including less than 20 weeks gestation)
System will initially be based on data from the states able to detect birth anomalies at least up to 1 year of age
- NSW, VIC, WA and SA
- further extending the period of detection in the future

(Modified from Australian Institute of Health and Welfare (AIHW))

Links: Australian Congenital Anomalies Monitoring System (ACAMS) | Australian Institute of Health and Welfare (AIHW)

Teratology

Now consider how different environmental effects during pregnancy may influence developmental outcomes. The terms listed below are often used to describe these environmental effects

Teratogen (Greek, teraton = monster) any agent that causes a structural abnormality (congenital abnormalities) following fetal exposure during pregnancy. The overall effect depends on dosage and time of exposure. (More? Critical Periods of Development)

Absolute risk the rate of occurrence of an abnormal phenotype among individuals exposed to the agent. (e.g. fetal alcohol syndrome)

Relative risk the ratio of the rate of the condition among the exposed and the nonexposed. (e.g. smokers risk of having a low birth weight baby compared to non-smokers) A high relative risk may indicate a low absolute risk if the condition is rare.

Mutagen a chemical or agent that can cause permanent damage to the deoxyribonucleic acid (DNA) in a cell. DNA damage in the human egg or sperm may lead to reduced fertility, spontaneous abortion (miscarriage), birth defects and heritable diseases.

Fetotoxicant is a chemical that adversely affects the developing fetus, resulting in low birth weight, symptoms of poisoning at birth or stillbirth (fetus dies before it is born).

Synergism when the combined effect of exposure to more than one chemical at one time, or to a chemical in combination with other hazards (heat, radiation, infection) results in effects of such exposure to be greater than the sum of the individual effects of each hazard by itself.

Toxicogenomics the interaction between the genome, chemicals in the environment, and disease. Cells exposed to a stress, drug or toxicant respond by altering the pattern of expression of genes within their chromosomes. Based on new genetic and microarray technologies.

UNSW Embryology Links

Abnormal Development
Abnormal Development- Australian Statistics | Abnormalities by Systems
Prenatal Diagnosis
Genetic Abnormalities | Down Syndrome | Edwards Syndrome | Fragile X | Lesch-Nyhan Syndrome
Maternal Factors | Maternal Diabetes | Maternal Hyperthermia | Neural Tube Defects | Fetal Alcohol Syndrome | Smoking | Chemical | Drugs | Illegal Drugs | Radiation | Heavy Metal | Iodine Deficiency | Viral Infection | Rubella | Polio | Parvovirus | Varicella | Bacterial Infection | Malaria | Toxoplasmosis | Autism
Fetal Origins Hypothesis
Intrauterine Growth Retardation
Twinning

External Links

Glossary Links

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Cite this page: Hill, M.A. (2024, June 2) Embryology Abnormal Development - Thalidomide. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development_-_Thalidomide

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