Teratogens and the Damage They Do

The Greek word for “Malformation or Monstrosity” is teras. This is the root of the words, teratogen and teratology. The study of teratogens is vital to the future health of newborns. The incidence of birth defects – some horrific in nature – can be lessened, but only if they can be isolated as a root cause of a particular abnormality. Some of the defects include severe mental retardation, cleft palates, and sadly, the birth of a baby with no arms or legs. Teratology is therefore, important for the futures of embryos and fetuses at risk. There are many teratogens that have been identified, but there are many more that remain anonymous. Those teratogens that have been identified are specific as to the anomalies they cause. Part of the problem with research is ethical in nature. For this reason, animals must take the place of humans in research. While not a perfect substitution by any means, it can lead research in the right direction. There are also a number of things that pregnant women can do to minimize the odds of these abnormalities occurring.

Teratology Background Information

How professional Define Teratogens

A look at how professionals in the field define teratogens and teratology is fairly consistent. According to Laura E. Berk, a teratogen is, “any environmental agent that causes damage during the prenatal period.” Writing for Columbia University, Dr. Wendy Chung defines teratology as, “the study of abnormal development in embryos and the causes of congenital malformations or birth defects.” Finally, The Children’s Hospital of Wisconsin’s website simply states that, “A teratogen is an agent, which can cause a birth defect.” Sometimes, simplicity is best to describe something that’s complicated.

A Brief History

The history of teratology dates back to 1867 when physician and bacteriologist Robert Koch began experimenting with anthrax, and found that it was capable of causing disease – and that the disease was transferable from one host to another. In efforts to find a causal relationship between a specific agent and a specific disease, he used various criteria that he hypothesized were necessary for this determination.

In 1890, he created a checklist of sorts known as Koch’s Postulates which states the following:

“A scientist must find the same microbe in every person with a given disease. Furthermore, the specific microbe must be able to be grown on pure culture medium in the lab and when reintroduced into a healthy animal or person must produce the disease again.” Koch’s Postulates became the starting point for many studies, but they were not perfect. One important factor that runs in opposition to the postulates is the fact that a virus needs a living cell to replicate. Obviously, this implies that it would not be capable of growing in a culture without a host cell to invade. Despite the flawed criteria, Koch is often credited with being the first to prove that diseases are caused by microbes.

The Science of Teratology

An Overview

Teratology is a scientific discipline that has grown in scope and stature since its inception. It is based in the belief that abnormalities in embryo and fetal development are caused, in some cases, by external or environmental sources. While many of the malformations are noticeable at birth, there are a comparable number that develop later in life – even though they were present at birth. These defects range in severity from inconsequential, like ear tags, to major, like missing limbs. Also of significance: “The greater the number of minor malformations, the greater the likelihood of an associated major malformation.”

The Timing of Teratogn Introduction

During embryonic and fetal development, there are critical periods when the embryo or fetus is most susceptible to foreign agents. The timeframe when certain organs and body parts are at the peak of their development, is also the timeframe when these same organs and body parts are most in danger of being adversely affected by the introduction of a teratogen. According to Dr. Chung, “The embryo is most susceptible to teratogenic agents during periods of rapid differentiation.” And from their article, Human Teratogens: A Critical Evaluation, written for the Motherisk Program at the Hospital for Sick Children in Toronto, Orna Diav-Citrin, M.D. and Gideon Koren, M.D., FACCT, FRCPC specifically note the following: “Teratogens act with specificity in that they produce specific abnormalities at specific times during gestation.”

The specificity with regard to when a teratogen is introduced is of utmost import. An example from the Children’s Hospital of Wisconsin states that a teratogen that “has the potential to interfere with the closure of the neural tube… exposure to the teratogen must occur in the first 3.5 to 4.5 weeks of the pregnancy, since this is when the neural tube is closing.” This is particularly serious as the neural tube becomes the brain and spinal cord. Common defects resulting from this are spina bifida and anencephaly. One can see that there is a small window of opportunity for a teratogen to be introduced – approximately one week in which the neural tube is closing. Other teratogens are capable of affecting other parts simultaneously or at other times depending on the organ or body part in the rapid development stage. It is also believed that two or more teratogens are responsible for various birth defects at various times – in various conditions. These multiple invasive agents merge in specific combinations to facilitate the formation of abnormalities.

The most susceptible period for a teratogen to cause damage during a pregnancy is in the embryonic stage which covers the first eight weeks. This is the phase when the most development takes place. By the time that fetal growth occurs, most (but not all) critical periods of development have passed. For example, the heart and limbs are fully formed by the end of the embryonic stage. The ears, eyes, teeth, and palate are nearly complete – although they are still developing, and therefore remain at risk during the fetal stage. The central nervous system is exposed throughout the pregnancy, but at high risk only until the 20th week, approximately.

Teratogen-linked Malformations

Teratogens are Responsible for a wide range of Abnormalities

Teratogens have been linked to various birth defects, and abnormalities of all levels of severity. Some congenital abnormalities include, but are certainly not limited to heart disease, mental retardation, cognitive problems, missing or malformed limbs, and all forms of cancer.

It is also recognized that congenital defects are not uncommon. It is estimated that between 1-3% of the general population are born with major defects. That statistic rises to approximately 5%, or one in twenty, when adult abnormalities are considered, and believed to have been present at birth. Of all major birth defects, about 25% are thought to be genetic in origin. A full 65% have an etiology, or origination, that is unknown. The remaining 10% are suspected of being caused by environmental exposures, including radiation and infections.

Teratogens are also target-specific. That is, they do not affect each organ or limb equally. Different teratogens attack different body parts at different times. For example, thalidomide can cause disfigured or missing limbs if taken during the early embryonic stage – as early as week four. Exposure to a virus during the embryonic stage is capable of causing mental retardation, eye cataracts, deafness, urinary, genital, heart, and intestinal defects. On the other hand, if the exposure happens in the fetal stage, damage is less likely to occur. One of the most tragic teratogens has to be alcohol, because it is 100% avoidable. It can cause mental retardation and other anomalies throughout the pregnancy.

Causal Teratological Factors

Defect-Related Variability

The amount of damage caused by teratogens is dependent on other variables such as heredity, dose, and other factors. Heredity is important in that it matters how a particular person reacts to an environmental reactant – everyone is different. Logically, dose makes a difference as well – the larger the dose, the greater the harm. Exposure to radiation, environmental pollutants, and smoke from tobacco products – even second-hand smoke are also risk factors. The consumption of alcohol, prescription and illegal drugs are also capable of causing multiple birth defects.

Radiation Exposure

Exposure to radiation during pregnancy can be particularly dangerous. The bombings of Hiroshima, Nagasaki, and the Chernobyl nuclear power plant accident in Ukraine, caused untold damage to those born to women who were pregnant during the events. Slow physical growth, underdeveloped brains, and extreme physical deformities are some of the malformations that were caused by the exposure. Even a seemingly-innocent X-ray has been known to be responsible for an increase in childhood cancer.


The environment is literally filled with man-made, as well as naturally-occurring pollutants. Mercury, PCBs, lead, and thousands of other substances have been introduced into the environment – and many new ones are released each and every year. Mercury has been in our water supplies and oceans since the 1950s when various industrial plants released waste containing it. Children have been born with many abnormalities as a result. Physical deformities, lack of coordinated movements, and mental retardation have all been traced to mercury. Even today, most fish contain a certain amount of mercury – some more than others. Sixty years later, pregnant women are still advised to avoid eating fish – in particular, swordfish, tuna, and shark.


PCBs were used in electrical equipment. Like mercury, they ended up in the food chain as a result of being released as waste. Low birth weight, smaller heads, problems with skin, gums, and nails have all been linked to even low levels of PCB contamination. Taiwan has been especially hard hit by PCB pollution in the form of rice-oil.


Until the 1980s, lead was an ingredient in most paint. Older buildings still have lead-based paint covering the walls. Some of the problems associated with lead exposure include brain damage, low birth weight, and many various physical defects. Lead has also been shown to be the root cause of antisocial behavior in adolescents.


Thankfully, smoking while pregnant is not nearly as widespread as it once was. The American Heart Association and others have helped tremendously as far as making consumers aware of the dangers of smoking. Obviously, while no amount of smoking is healthy, the risks are without doubt, dose-related. The more one smokes – or is exposed to smoke – the greater the potential damage to the embryo and fetus. Smoking mothers are more likely to have newborns who are unresponsive, have increased muscle tension, low birth weight, impaired heart rate, and asthma, as well as a greater likelihood of cancer in later childhood. Even passive smokers – those who don’t smoke themselves, but are affected by those around them – are in danger of having babies with low birth weight, respiratory illnesses, and long-term attention impairment.


Consuming alcohol is a very bad idea for pregnant women. Fetal alcohol syndrome, partial fetal alcohol syndrome and other alcohol-related conditions are especially tragic in that they are completely avoidable. Alcohol is known to be a causal factor for babies with a plethora of abnormalities ranging from slight to extreme, and everything in between. Much of the deformities depend on how much and how often the mother drank. Slow growth, brain damage, and problems involving the heart, immune system, genitals, eyes, ears, nose, throat, are all possibilities. Other problems resulting from alcohol consumption include the development of impaired judgment, poor motor skills, inappropriate sexual behavior, mental health issues, and other problems.


Drugs, as prescribed by a doctor, are generally safe for the mother, but the same cannot be said of the embryo or fetus. All drugs – legal or illegal – have the potential to harm the unborn. As a result, all pregnant women are advised to avoid all medication unless absolutely necessary during the first eight weeks.

Discussion and Conclusion

Research Studies

It should be obvious that there are no studies involving human testing for ethical reasons. Animals, while not human, and with different gestational periods, are used to test drugs and suspected teratogens. If more than one species shows the same susceptibility to a particular teratogen, it is generally assumed that there is good possibility that there exists a potential threat to humans. The only studies involving humans are necessarily retrospective in nature. That is, once an abnormality has been identified in a newborn, there is the difficult and time-consuming task of retracing the steps of the mother since conception. Today, this is still, in essence, the only way of searching for, and discovering a possible causal link to a teratogen.

Drug Categorization

In 1980, drug companies began to categorize their products – labeled by potential threat level to the unborn. There were five categories ranging from category A which states that the medication has shown no ill effects, to category X, which states the medication is linked to certain birth defects, and therefore should not be used by pregnant women. While this seemed to be a logical step to assure the highest degree of safety possible, some professionals complained that the pharmaceutical companies were perhaps more worried about lawsuits than birth defects resulting from the use of their products. However, the existence of category X does offer concrete evidence, and shows what to avoid – as known fetal abnormalities have been shown in both humans and animals. So, while not perfect, and sometimes confusing, the labeling would appear worthy of keeping – and improving.

Minimizing Risk

It’s clear that healthy pregnancies are dependent on a myriad of factors. There is no way of eliminating absolutely, the possibility of a congenital malformation. Short of living in a self-contained environmental bubble, it just cannot be accomplished. Risks can be reduced however, by using common sense during a pregnancy. Being careful of what one ingests – including prescription drugs; avoiding alcohol, tobacco, and other toxins – as well as those in the environment is crucial. It’s also important to eliminate any prescribed drugs that are not medically essential.

Teratogens are virtually everywhere. They are in the food we eat, the water we drink, and the air we breath. While there are obvious differences in food contaminants, fish and raw or undercooked meat should be avoided. Many people have less control over the water they drink, but purified bottled water is obviously preferable to common tap water – especially in underdeveloped areas. Breathing air certainly cannot be helped, but avoiding high pollution zones would be wise. Today, there are more environmental teratogens than ever before – with more introduced every day. While progress is being made, research unfortunately, is lagging far behind – mainly due to the ethical limitations inherent in the studies.

Equine Assisted Therapy – Working Small Miracles Every Day

Man has known the value of the horse for thousands of years. The horse has been by his side helping him no matter what the task, never letting him down. Once again we ask the horse to work with us, and now more than ever we count on their grace, their strength, and even their emotions to help us heal both physically and mentally. The horse could not be more perfect for this job.

Equine Assisted Therapy (EAT) combines the use of the horse and their surroundings to improve the physical, mental, and behavioral well-being of all people. EAT not only increases strength, flexibility, balance, and fine motor skills for someone with Down syndrome or a traumatic brain injury, but EAT can also help an adolescent learn how to deal with frustration, anger, and low self-esteem. EAT helps people from all walks of life in a wide variety of ways.

GRACE Rides, Inc. is a non-profit 501c3 organization located in Niceville FL that offers EAT for the Okaloosa and Walton county area. GRACE Rides is a North American Riding for the Handicapped Association (NARHA) member center that adheres to strict rules and regulations to provide the highest professional safety standards possible. Trainers and therapists are specially certified. Volunteers are needed every day for different tasks including assisting the trainers, caring for the horses, cleaning the facilities, and maintaining the buildings and property. Volunteers are essential for a successful program!

The horses at GRACE Rides are specially selected and trained to participate in the EAT program. Each horse is then carefully matched with a therapy participant based on the horses’ size, temperament, and any medical necessities that may be required for each participant. When a person first meets a horse, they must develop a bond of trust. Since a horse can sense our feelings, they react to however we are feeling that day. If a participant is feeling angry and aggressive the day they come to participate in the program, the horse will typically respond with fear and will be uncooperative until the participant resolves his/her emotions.

I have been honored to be a part of the horse world my entire life. When I was a child I learned how important it is to bond with each horse. Each horse speaks in a different way and you just have to be there to listen to them. Now I’m blessed to be working as an instructor with the horses at GRACE Rides to use my lifetime’s work with horses and my knowledge of the human body to help people in any way that I can. Whether I’m teaching a child to brush a horse for the first time; jump a horse for the first time; or even touch a horse for the first time; every step is special in my eyes and I wouldn’t miss it for the world. Some of the people we work with have a hard time at physical therapy during the week, but they can’t wait for their session with the horses. Riding is hard work but you would never know it. Hands too tight to hold the reins start loosening up; muscles start stretching out from the warmth of the horse; and because of all the excitement, words start flowing from mouths that typically don’t speak. These truly are small miracles.

The horse is such a large and magnificent creature! I am reminded every day that I am blessed to have horses in my life to share such a beautiful and unconditional love. Thank you to GRACE Rides for allowing me to combine my love for horses and my desire to make a difference in other people’s lives.

Electrical Muscle Stimulation Treatments for Cerebral Palsy

Ninety percent of children with cerebral palsy have muscle spasticity as their dominant or exclusive impairment. EMS (electrical muscle stimulation) is the elicitation of muscle contracture through electronic stimulation and is sometimes used to treat children with spastic cerebral palsy. When combined with the right physical therapies, experts have demonstrated that EMS can improve overall motor function, increasing the child’s ability to perform physical tasks such as walking.

There are two ways of approaching EMS. The first is called NMES (neuromuscular electrical stimulation) or FES (functional electrical stimulation). The procedure, done only by a medical professional, involves giving specific muscles or muscle groups short bursts of electrical impulses designed to mimic the normal communication between the brain and the muscular system. Hopefully this can retrain the muscles to respond appropriately to the desires of the brain in a way they frequently don’t in someone suffering from spastic CP.

TES (threshold electrical stimulation) is very different. It involves much lower voltage and can be directed at a specific muscle or muscle group over a long period of time. It can be administered by the patient or a family member and can even take place overnight while the patient sleeps. It does not induce contraction, but instead is used to relieve patients of some of the discomfort and pain that comes with spasticity.

The way that NMES works is that electrodes are placed onto the skin in the vicinity of the muscles that are either in atrophy or have weakened due to spasticity. The electrodes are connected to a small generator. The current is low and rarely causes discomfort to the patient. The intent is to force the muscle to contract in a way that the brain is failing. The response is not dissimilar to having your reflexes induced by tapping on the knee. With TES, the procedure can be administered by a parent at home.

Unfortunately, with spastic cerebral palsy, any improvements brought about by EMS are temporary. The damage to the neuromuscular system is irreversible and the brain really can’t be trained to stimulate the muscles appropriately on its own. In most cases, full-time relief from the impairment of muscle spasticity requires approximately 2 hours of EMS every day of the week. Even then, any prolonged break from treatment will probably result in the abnormal spasticity returning to pre-treatment levels. For many, the benefits, however temporary, are worth a lifetime of daily treatment.

Because of the temporal nature of the benefits, many experts in the cerebral palsy world consider electrical muscle stimulation only as a supplement to standard treatments. Exercise and physical activity are still seen as having more enduring benefits to the ultimate health and well-being of children with cerebral palsy. But the debate is ongoing. Other experts believe that with further advancements, EMS alone may be used to treat and improve, at least, the smaller muscle groups such as in the forearm or wrist. Whether or not EMS can one day stand alone as a treatment for EMS remains to be seen, but it is at least worth consideration as an element of your child’s physical therapy.

Isn’t ADHD Just An Excuse For Lack Of Discipline?

ADHD or Attention Deficit Hyperactivity Disorder is a disorder that commonly affects children by making them hyperactive with low attention span, it has been seen that boys are inflicted more than the girls. The typical symptoms include difficulty in controlled behavior, low focus and attention span and hyperactivity. But considering the increasing levels of behavioral issues plaguing schools and homes, isn’t ADHD just an excuse for a lack of discipline?

Attention Deficit Hyperactivity (ADHD) symptoms

Most parents of children diagnosed with ADHD complain of violent behavior patterns with children of 7 to 9 years hitting siblings and others that prevent them from doing things they want to do. As per studies conducted on ADHD and childhood behavior patterns, here are some of the common symptoms:

• Distraction

• Forgetfulness and daydreaming patterns

• Low attentions span

• Poor listening skills

• Poor concentration

• Heightened activity- running, inability to play quietly

• Aggressive and violent behavior

However, aggressive behavior and anger is a common pattern seen in young and older aged children diagnosed with this disorder. It has been seen that feelings of frustration coupled with lack of communication of emotions vent out as aggressive and violent behavior patterns.

Though they are developmentally delayed, it has been seen that the urge to resist aggressive behavior is lacking. But the fact that children have communication issues along with poor focus, reinforcement of instructions does help. But it is also seen in kids with poor discipline and lower levels of parental control.

Can poor parenting skills lead to misdiagnosis as ADHD?

But coming back to the question that isn’t ADHD just an excuse for a lack of discipline, it is true that in some cases, indiscipline is camouflaged by ADHD. Poor parenting skills compounded by lack of discipline can label the kids afflicted with ADHD. But not all children diagnosed with ADHD are categorized such due to lack of discipline. This is a serious behavioral disorder that continues to adulthood unless there is medical and therapeutic intervention. Though there is no cure for Attention Deficit Hyperactivity Syndrome, some medicines and behavioral therapy is advised by physicians depending upon individual evaluation.

Oftentimes, it is easy for parents to put the blame on the children citing medical disorders than introspecting on their own parenting skills. They take the child from doctor to doctors till the symptoms are correlated with a behavioral problem, which is one of the reasons that ADHD is misdiagnosed. Most of the children with such poor parenting and discipline issue, who are labeled as ADHD, get away with misbehavior. However, the children that are misdiagnosed and put on drugs suffer lifelong side-effects which could have been avoided with little discipline.

Thus, in a way, isn’t ADHD just an excuse for a lack of discipline? Yes, it is in some cases while in others, it is for the betterment of the child to receive proper guidance and therapy to enhance communication skills and increase focus. It is the role of parents to wisely notice the symptoms, stay balanced and the skill of the doctor to be able to diagnose correctly.