Common teratogens include some medications, recreational drugs, tobacco products, chemicals, alcohol, certain infections, and in some cases, uncontrolled health problems in the birthing parent. Alcohol is a well-known teratogen that can cause harmful effects on the fetus after exposure at any time during pregnancy.

What are 3 examples of teratogens?

  • angiotensin converting enzyme (ACE) inhibitors, such as Zestril and Prinivil.
  • alcohol.
  • aminopterin.
  • androgens, such as methyltestosterone (Android)
  • busulfan (Myleran)
  • carbamazepine (Tegretol)
  • chlorobiphenyls.
  • cocaine.

What role do teratogens play in birth defects?

A teratogen is any agent that causes an abnormality following fetal exposure during pregnancy. Teratogens are usually discovered after an increased prevalence of a particular birth defect. For example, in the early 1960’s, a drug known as thalidomide was used to treat morning sickness.

What are 4 teratogens?

Teratogens are classified into four types: physical agents, metabolic conditions, infection, and finally, drugs and chemicals. The word teratogen originates from the Greek word for monster, teratos.

What agents cause birth defects?

  • ACE (angiotensin converting enzyme) inhibitors.
  • angiotensin II antagonist.
  • isotretinoin (an acne drug)
  • alcohol.
  • cocaine.
  • high doses of vitamin A.
  • lithium.
  • male hormones.

Can drugs cause stillbirth?

Recent research shows that smoking tobacco or marijuana, taking prescription pain relievers, or using illegal drugs during pregnancy is associated with double or even triple the risk of stillbirth. Estimates suggest that about 5 percent of pregnant women use one or more addictive substances.

What is FASDs?

Fetal alcohol spectrum disorders (FASDs) are a group of conditions that can occur in a person who was exposed to alcohol before birth. These effects can include physical problems and problems with behavior and learning. Often, a person with an FASD has a mix of these problems.

What are teratogens give 5 examples?

A teratogen is something that can cause birth defects or abnormalities in a developing embryo or fetus upon exposure. Teratogens include some medications, recreational drugs, tobacco products, chemicals, alcohol, certain infections, and in some cases, health problems such as uncontrolled diabetes in pregnant people.

When is fetus most susceptible to teratogens?

The embryonic period, during which organogenesis takes place, occurs between implantation at around 14 days to around 60 days postconception. This is usually the most sensitive period to teratogenesis when exposure to a teratogenic agent has the greatest likelihood of producing a malformation.

When is the brain most likely to be harmed by teratogens?

Major malformations are more common in early embryos than in newborns; however, most severely affected embryos are spontaneously aborted during the first six to eight weeks of gestation. During organogenesis between days 15 to 60, teratogenic agents are more likely to cause major congenital malformations.

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What factors influence the effects of teratogens?

The effects depend on the nature of the teratogen, the timing at which the exposure occurs and, most likely, the genetic susceptibility of the mother and/or the fetus. Teratogenic agents can be environmental chemicals, maternal metabolic factors, drugs, or infections.

Which factor influences the effects of teratogens quizlet?

The impact of teratogens varies with amount and length of exposure, genetic make-up of mother and fetus, presence of other harmful agents, and age of the organism. The developing organism is especially vulnerable during the embryonic period.

Which teratogen is the leading cause of developmental disabilities?

Alcohol use (beer, wine, or hard liquor) during pregnancy is the leading cause of preventable birth defects and intellectual disabilities in the United States. Fetal alcohol syndrome and other FASDs can be prevented by not drinking any alcohol during pregnancy.

Can Down syndrome be caused by teratogens?

Some are recognizable genetic disorders (such as Down syndrome and muscular dystrophy), some are caused by known teratogens (eg: alcohol, rubella), and many have no identifiable cause.

What causes birth defects in first trimester?

These defects can be very minor or severe and typically develop in the first three months of pregnancy. About 70% of the time, the cause of the defect is not known. However, known causes of birth defects can also include genetics or exposure of the mother to harmful agents or medications.

What is the difference between FASD and FAS?

FASD is a broader diagnosis that encompasses patients with FAS and others who are affected by prenatal alcohol exposure but do not meet the full criteria for FAS.

What is an alcohol binge?

The National Institute on Alcohol Abuse and Alcoholism defines binge drinking as a pattern of drinking alcohol that brings blood alcohol concentration (BAC) to 0.08 percent—or 0.08 grams of alcohol per deciliter—or higher.

Can you tell if a baby has FAS in the womb?

Although doctors can’t diagnose fetal alcohol syndrome before a baby is born, they can assess the health of the mother and baby during pregnancy. Watches for signs and symptoms of fetal alcohol syndrome in your child’s initial weeks, months and years of life.

What is the most common cause of stillbirth?

Failure of the placenta is the most common known reason for a baby to be stillborn. About half of all stillbirths are linked to complications with the placenta.

What happens if a newborn tests positive for drugs?

Exposure to maternal drug use during gestation may adversely affect neonatal development and may lead to acute adverse events, including neonatal abstinence syndrome (NAS) and infant mortality. Prenatal drug exposure may also contribute to long-term behavioral effects and developmental deficits.

What happens if a baby is born with drugs in it's system?

It may not be detected at the time of birth. Other drugs may cause birth defects involving the heart, brain, bowel, or kidneys. Babies who have been exposed to drugs, alcohol, or tobacco are at higher risk for SIDS (sudden infant death syndrome).

What causes abnormalities in baby during pregnancy?

A birth defect is something visibly abnormal, internally abnormal, or chemically abnormal about your newborn baby’s body. The defect might be caused by genetics, infection, radiation, or drug exposure, or there might be no known reason.

What is the most prevalent cause for small gestational age SGA babies?

What causes SGA? Although some babies are small because of genetics (their parents are small), most SGA babies are small because of fetal growth problems that occur during pregnancy. Many babies with SGA have a condition called intrauterine growth restriction (IUGR).

Which teratogenic drugs cause hand eye defects?

The combination of valproic acid, carbamazepine, and phenytoin or phenobarbital seems to have the highest risk. The diphenylhydantoin syndrome occurs in 5% to 10% of babies born to a mother under therapy with the drug.

What are four environmental hazards that can affect a fetus?

These chemicals include commonly known hazards such as lead, mercury, and environmental tobacco smoke, as well as some pesticides, solvents, products containing chlorine, and other chemicals referred to as “persistent organic pollutants.” The fetus is particularly vulnerable to environmental chemicals that can disrupt …

What types of infectious agents are teratogens?

Teratogenic agents include infectious agents (rubella, cytomegalovirus, varicella, herpes simplex, toxoplasma, syphilis, etc.); physical agents (ionizing agents, hyperthermia); maternal health factors (diabetes, maternal PKU); environmental chemicals (organic mercury compounds, polychlorinated biphenyl or PCB, …

What are the causes of Teratology?

  • Toxic substances, such as, for humans, drugs in pregnancy and environmental toxins in pregnancy. Potassium iodide is a possible teratogen. …
  • Vertically transmitted infection.
  • Lack of nutrients. …
  • Physical restraint. …
  • Genetic disorders.
  • Alcohol consumption during pregnancy.

Which of the following occurs during the germinal stage?

The germinal period (about 14 days in length) lasts from conception to implantation of the zygote (fertilized egg) in the lining of the uterus. During this time, the organism begins cell division and growth. After the fourth doubling, differentiation of the cells begins to occur as well.

Do the effects of behavioral teratogens last a lifetime?

A look at some teratogens Alcohol consumption, particularly during the second month of prenatal development but at any point during pregnancy may lead to neurocognitive and behavioral difficulties that can last a lifetime.

How teratogens cause genetic and congenital birth defects in babies?

As a baby grows in the womb, teratogens may affect parts of the baby’s body as they are forming. For example, the neural tube closes in the first 3 to 5 weeks of the pregnancy. During this time, teratogens can cause neural tube defects such as spina bifida.

Which teratogen is the leading cause of developmental disabilities quizlet?

Prenatal toxins Exposure to alcohol in utero is the most common teratogenic cause of developmental disabilities, including microcephaly, cognitive disability, learning disabilities, ADHD and behavioural challenges.