get potential female AIDS victims to take the proper
precautions and avoid sexual relationships with high-
risk males, usually those involved with drugs. Signifi-
cant progress was being made, especially concerning
children.
Toxemia is a frightening condition that is poten-
tially fatal for the mother and the fetus. It is character-
ized by high blood pressure, swelling, and weight gain
due to a buildup of fluid in the body tissues, and the
presence of protein in the mother’s urine. In severe
cases the woman may go into convulsions or coma,
placing a tremendous strain on her, which is carried
over to the fetus. Women with toxemia frequently give
birth to premature babies or to babies smaller than
average for their gestational age. Like many other
types of blood-pressure disorders, however, toxemia
can be treated through medication and diet.
Anoxia is a condition in which the brain of the
baby does not receive enough oxygen to allow it to de-
velop properly. Anoxia can cause certain forms of epi-
lepsy, mental deficiency, cerebral palsy, and behavior
disorders. If the amount of brain damage is not too
severe, however, it may be possible to compensate for
the disorder to some extent. Epilepsy can often be
controlled with drugs, for instance, and many chil-
dren with cerebral palsy can learn to control their af-
fected muscles.
Age
Teenage mothers and those over thirty-five years
of age have a higher risk of miscarriage, premature
birth, and some birth defects than mothers in the
prime childbearing years. Some of the reasons are
fairly obvious. Very young mothers have not yet com-
pleted their own development, and the reproductive
system may not be quite ready to function smoothly
or effectively. In older women the reproductive sys-
tem may be past its most efficient functioning.
In both cases, pregnancy puts an extra strain on
a body that is not fully able to bear it. Furthermore,
there is some reason to think that a woman’s ova may
deteriorate with age, leading to a greater risk of birth
defects. Women have all their ova in partly developed
form when they are born. So a woman who becomes
pregnant at age thirty-seven, for example, is ‘‘using’’
an ovum that has been more or less exposed to thirty-
seven years’ worth of harmful chemicals, radiation,
virus infections, and whatever else has happened to
her body. This may explain why, for instance, Down
syndrome is most common in children born to moth-
ers over forty years of age.
It is quite possible that men’s sperm may also be
susceptible to chemicals and radiation effects over
time. Furthermore, there may be genetic disorders
that cause changes in sperm structure.
Diet and Physical Condition
Just as other aspects of physical health are impor-
tant, so is the mother’s diet. While physicians and re-
searchers have long realized that pregnancy puts
additional demands on the mother’s body, they used
to assume that the fetus’ nutritional needs would be
met first, even at the mother’s expense.
The current opinion, however, is that the prena-
tal development of the fetus and its growth and devel-
opment after birth are directly related to maternal
diet. Women who follow nutritionally sound diets
during pregnancy give birth to babies of normal or
above-normal size. Their babies are less likely to con-
tract bronchitis, pneumonia, or colds during early in-
fancy and have better developed teeth and bones.
The mothers have fewer complications during preg-
nancy and, on the average, spend less time in labor.
The less time in labor, the easier the birth and the less
stress the mother and child experience.
But if the mother’s diet is low in certain vitamins
and minerals when she is pregnant, the child may suf-
fer from specific weaknesses. Insufficient iron may
lead to anemia in the infant, and a low intake of calci-
um may cause poor bone formation. If there is an in-
sufficient amount of protein in the mother’s diet, the
baby may be smaller than average and may suffer
from mental retardation, with almost 20 percent
fewer brain cells. Mothers who are also physically
small (under 100 pounds [45 kilograms] in total body
weight) are risky for pregnancy as well because of the
stress that pregnancy can place on them.The Rh Factor
The Rh-positive factor is an inherited genetically
dominant trait in the blood that can result in a dan-
gerous situation for the fetus. When blood containing
the Rh factor (that is, Rh-positive blood) is introduced
into blood without the Rh factor (Rh-negative blood),
antibodies to combat the Rh factor are produced. If
an Rh-negative woman mates with an Rh-positive
man, the resulting child may have Rh-positive blood.
Any small rupture in the capillaries of the placenta
will release the Rh factor into the mother’s blood-
stream, causing her body to produce the antibodies
needed to fight it. The antibodies in the mother’s
blood will then cross the placenta into the fetal blood-
stream and attack its Rh-positive red blood cells, de-
priving the fetus of oxygen. The result may be a
miscarriage, possible brain defects, or even death to
the fetus or newborn child. Only in circumstances in-
volving an Rh-negative mother and an Rh-positive
child does this danger exist.
This condition in the child is called fetal
erythroblastosis. Firstborn children are not threat-
ened, because the mother’s blood has not had time to332 PRENATAL DEVELOPMENT