Prenatal Development -
Prenatal Environmental Influences
During the first three
months of pregnancy, tissues and important body systems develop in the embryo.
Adverse influences during this period will affect the basic structure and form
of the body and may have particularly serious effects on the nervous
system.
Teratogens
The
scientific study of congenital abnormalities caused by prenatal environmental
influences is known as teratology (from the Greek word teras, meaning
"marvel" or "monster"), and the environmental agents that
produce abnormalities in the developing fetus are called teratogens.
Drugs
The severity
of the abnormality depends on the amount of the chemical the mother is exposed
to, the developmental stage of the fetus, and the period of time over which the
mother's exposure to the chemical takes place.
In terms of
narcotics, women who are addicted to heroin, morphine, or methadone give birth
to addicted babies. Soon after birth, the babies show symptoms of withdrawal,
including tremors, convulsions, difficulty breathing, and intestinal
disturbances.
Smoking and Nicotine
Cigarette
smoking has already been shown to have dire consequences for the smoker, and it
can be hazardous for the fetus and the newborn child.
Maternal
smoking increases the risk of spontaneous abortions, bleeding during pregnancy,
prematurerupture of the amniotic sac, and fetal deaths and deaths of
newborns.
Alcohol
The effects
of alcohol are almost undisputed. And it is not just the heavy drinker
who may place her fetus in danger. It has been found that women having one or
more drinks daily were three times more likely to miscarry than women who had
less than one drink daily.
Other
possible complications include permanent growth retardation, malformations of
the face, brain damage, hyperactivity and learning disabilities, and heart
defects.
Results of
research also indicate that moderate drinking can affect the later development
of a child's intelligence as measured by IQ scores at age four.
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