Prenatal Environmental Influences
What are teratogens, and what factors influence their impact?
Teratogens are environmental agents that cause damage during the prenatal period. Their impact varies with the amount and length of exposure, the genetic makeup of mother and fetus, the presence or absence of other harmful agents, and the age of the organism at time of exposure. The developing organism is especially vulnerable during the embryonic period. In addition to immediate physical damage, some health outcomes may appear later in development, and physical defects may lead to psychological consequences as well.
Teratogens are environmental agents that cause damage during the prenatal period. Their impact varies with the amount and length of exposure, the genetic makeup of mother and fetus, the presence or absence of other harmful agents, and the age of the organism at time of exposure. The developing organism is especially vulnerable during the embryonic period. In addition to immediate physical damage, some health outcomes may appear later in development, and physical defects may lead to psychological consequences as well.
List agents known to be or suspected of being teratogens, and discuss evidence supporting their harmful impact.
Drugs, cigarettes, alcohol, radiation, environmental pollution, and infectious diseases are teratogens that can endanger the developing organism. Currently, the most widely used potent teratogen is Accutane, a drug used to treat severe acne. The prenatal impact of many other commonly used medications, such as aspirin and caffeine, is hard to separate from other factors correlated with drug taking. Babies born to users of heroin, methadone, or cocaine are at risk for a wide variety of problems, including prematurity, low birth weight, physical defects, and breathing difficulties around the time of birth.
Infants whose parents use tobacco are often born underweight and have attention, learning, and behaviour problems in early childhood. Maternal alcohol consumption can lead to fetal alcohol spectrum disorder (FASD). Fetal alcohol syndrome (FAS) involves slow physical growth, facial abnormalities, and impairment in mental functioning. Milder forms -partial fetal alcohol syndrome (p-FAS) or alcohol-related neurodevelopmental disorder (ARND)- affect children whose mothers consumes smaller quantities of alcohol.
Prenatal exposure to high levels of radiation, mercury, lead, dioxins, and PCBs leads to physical malformations and severe brain damage. Low-level exposure to these teratogens has also been linked to diverse impairments, including cognitive deficits and emotional and behavior disorders.
Among infectious diseases, rubella causes a wide variety of abnormalities. Babies with prenatally transmitted HIV rapidly develop AIDS, leading to brain damage and early death. Cytomegalovirus, herpes simplex 2, and toxoplasmosis can also be devastating to the embryo and fetus.
Describe the impact of other maternal factors on prenatal development.
Regular moderate exercise during pregnancy contributes to general health and readiness for childbirth and is related to higher birth weight. However, very rigorous exercise results in lower birth weight. When the mother's diet is inadequate, l ow birth weight and damage to the brain and other organs are major concerns. Vitamin - mineral supplementation, including folic acid, before conception and continuing during pregnancy can prevent prenatal and birth complications. Severe emotional stress is linked to many pregnancy complications and may permanently alter fetal neurological functioning, resulting in anxiety, short attention span, behavior problems and lower mental tests scores in childhood. The negative impact of prenatal stress can be reduced by providing the mother with emotional support. Rh factor incompatibility - an Rh-positive fetus developing within an Rh-negative mother - can lead to oxygen deprivation, brain and heart damage, and infant death. Aside from the risk of chromosomal abnormalities in older women, maternal age through the early forties is not a major cause of prenatal problems. Poor health and environmental risks associated with poverty are the strongest predictors of pregnancy complications in both teenagers and older women.
Why is early and regular health care vital during the prenatal period?
Unexpected difficulties, such as preeclampsia, can arise, especially when pregnant women have health problems to begin with. prenatal care is especially crucial for those women least likely to seek it - in particular, those who are young or poverty-stricken. among low- SES ethnic minority mothers, culturally sensitive health- care practices - such as group prenatal care - can lead to more health-promoting behaviors.
Drugs, cigarettes, alcohol, radiation, environmental pollution, and infectious diseases are teratogens that can endanger the developing organism. Currently, the most widely used potent teratogen is Accutane, a drug used to treat severe acne. The prenatal impact of many other commonly used medications, such as aspirin and caffeine, is hard to separate from other factors correlated with drug taking. Babies born to users of heroin, methadone, or cocaine are at risk for a wide variety of problems, including prematurity, low birth weight, physical defects, and breathing difficulties around the time of birth.
Infants whose parents use tobacco are often born underweight and have attention, learning, and behaviour problems in early childhood. Maternal alcohol consumption can lead to fetal alcohol spectrum disorder (FASD). Fetal alcohol syndrome (FAS) involves slow physical growth, facial abnormalities, and impairment in mental functioning. Milder forms -partial fetal alcohol syndrome (p-FAS) or alcohol-related neurodevelopmental disorder (ARND)- affect children whose mothers consumes smaller quantities of alcohol.
Prenatal exposure to high levels of radiation, mercury, lead, dioxins, and PCBs leads to physical malformations and severe brain damage. Low-level exposure to these teratogens has also been linked to diverse impairments, including cognitive deficits and emotional and behavior disorders.
Among infectious diseases, rubella causes a wide variety of abnormalities. Babies with prenatally transmitted HIV rapidly develop AIDS, leading to brain damage and early death. Cytomegalovirus, herpes simplex 2, and toxoplasmosis can also be devastating to the embryo and fetus.
Describe the impact of other maternal factors on prenatal development.
Regular moderate exercise during pregnancy contributes to general health and readiness for childbirth and is related to higher birth weight. However, very rigorous exercise results in lower birth weight. When the mother's diet is inadequate, l ow birth weight and damage to the brain and other organs are major concerns. Vitamin - mineral supplementation, including folic acid, before conception and continuing during pregnancy can prevent prenatal and birth complications. Severe emotional stress is linked to many pregnancy complications and may permanently alter fetal neurological functioning, resulting in anxiety, short attention span, behavior problems and lower mental tests scores in childhood. The negative impact of prenatal stress can be reduced by providing the mother with emotional support. Rh factor incompatibility - an Rh-positive fetus developing within an Rh-negative mother - can lead to oxygen deprivation, brain and heart damage, and infant death. Aside from the risk of chromosomal abnormalities in older women, maternal age through the early forties is not a major cause of prenatal problems. Poor health and environmental risks associated with poverty are the strongest predictors of pregnancy complications in both teenagers and older women.
Why is early and regular health care vital during the prenatal period?
Unexpected difficulties, such as preeclampsia, can arise, especially when pregnant women have health problems to begin with. prenatal care is especially crucial for those women least likely to seek it - in particular, those who are young or poverty-stricken. among low- SES ethnic minority mothers, culturally sensitive health- care practices - such as group prenatal care - can lead to more health-promoting behaviors.