Methods of Impregnation
-If this is unsuccessful, couples and their doctors may proceed to artificial
insemination, which involves injecting sperm, either from a womans partner or
from a donor, into her uterus.
-Or they may use in vitro fertilization (IVF
-Nonetheless, this tiny being can swallow, digest food, and urinate.
-All this behaving contributes to the proper development of the nervous system,
digestive system, and other systems of the body, and it is consistent with the
-Under a doctors close supervision, medications used to treat ailments and
medical conditions are usually safe for mother and fetus.
-However, certain individuals exposed to certain drugs in certain doses at certain
times during the prenatal pe
-A membrane called the placental barrier allows these small molecules to pass
through, but it prevents the large blood cells of embryo and mother from
-It also protects the developing child from many harmful substances, but as
-Fetuses whose heart rates and movements were concordant (that is, matched)
at 36 weeks showed better regulation of their behavioral states at 2 weeks old.
They were more alert, less irritable, better able to sustain there attention,
Pregnancies and DIseases
-Nearly 15% of pregnant women with rubella miscarry or experience a fetal death
-Birth defects occur in 6085% of babies whose mothers had the disease in the
first 2 months of pregnancy, in about 50% of those infected in the third
-The important process of sexual differentiation begins during the seventh and
eighth prenatal weeks.
-First, undifferentiated tissue becomes either male testes or female ovaries: if the
embryo inherited a Y chromosome at conception, a gene o
-Anoxia is dangerous primarily because brain cells die if they are starved of
oxygen for more than a few minutes.
-Severe anoxia can initially cause poor reflexes, seizures, heart rate
irregularities, and breathing difficulties.
-In the lon
-Neurons migrate to the closest or innermost parts of the brain first and to the
farthest or outermost parts last, and much of this occurs between 8 and 15
weeks after conception.
-In addition to multiplication and migration of cells, diff
-This prenatal development is divided into three stages or periods: the germinal
period, the embryonic period, and the fetal period.
-When the blastocyst reaches the uterus around day 6, it implants tendrils from
its outer layer into the
-Midway through the menstrual cycle, every 28 days or so, females ovulate: an
ovum (egg cell) ripens, leaves the ovary, and begins its journey through the
fallopian tube to the uterus.
-Usually the egg disintegrates and leaves the body as part
-Alcohol consumed by the mother readily crosses the placenta, where it can
directly affect fetal development and disrupt hormone functions of the placenta
-Prenatal alcohol exposure disrupts the normal process of neuronal migration,
leading to several