The Developing Child Chapter 5 Section 3 P ROBLEMS IN P RENATAL D EVELOPMENT

L OSING A B ABY  Sometimes a baby does not develop normally. In some of those cases, the developing baby dies.  Miscarriage- death that occurs before 20 weeks of pregnancy.  Stillbirth- death that occurs after 20 weeks of pregnancy.  The loss of a baby brings shock and pain to the family.  Families go through the same stages of grief as they would if any family member died.

T YPES OF B IRTH D EFECTS  Birth Defects- serious problems that threaten a babies health or ability to live.  There are 100’s of different birth defects. Their effects have a wide range. Some can be corrected immediately while others cannot.  Approximately 3 out of every 100 children born in the U.S have a birth defect.  Some birth defects affect the shape or size of the body.  Others affect the function of the body’s systems.  Not all birth defects can be detected right away.

C AUSES OF B IRTH D EFECTS  Scientist are constantly researching to find out what causes birth defects.  The cause of about 60% of birth defects is unknown.  Through their research they have found that there are 4 main causes for birth defects:  Environmental Causes  Heredity Causes  Errors in Chromosomes  Interaction between Environment & Heredity

E NVIRONMENTAL C AUSES  During the first few weeks of pregnancy, a baby develops all the bodily systems needed for survival and normal life.  Many choices the mother makes can greatly affect the development of her baby:  The nutritional balance of her diet  Diseases or infections mother is introduced to  Harmful substances such as alcohol, tobacco, and drugs  Some medications that benefit mom, but not baby  Exposure to hazards such as radiation etc.

H EREDITY C AUSES  1,000’s of genes make up our genetic blueprint.  For each person, 5 or 6 of the recessive genes are imperfect. A single copy of these genes will have no effect on development.  Sometimes, two defective recessive genes are pass on, or a defective dominate gene is passed on- causing a birth defect.  Some birth defects affect only one sex.

E RROR IN C HROMOSOMES  A few birth defects are linked to a problem with the baby’s chromosomes.  There may be too many or too few chromosomes.  These types of defects are not inherited.  Down Syndrome is the most common type of birth defect caused by errors in chromosomes.  1 out of every 800 children are born with Down Syndrome.  The risk is increased significantly if the mother is over 35.  A child with Down Syndrome has an extra chromosome 21.

I NTERACTION OF H EREDITY & E NVIRONMENT  Some birth defects result from heredity & environment working together.  For example, a baby may inherit a tendency for a heart defect. This defect appears only if some factor- such as a drug or a virus- affect the baby during his or her development.  If the environmental factor was avoided, then the heart defect would not have appeared.  Researchers believe that interaction of heredity & environment is probably the cause for cleft palate, and spina bifida.  Taking extra folic acid during pregnancy can prevent spina bifida.

P REVENTION OF B IRTH D EFECTS  It can be difficult for a child born with a birth defect to live a normal life.  The rest of the family is affected by the emotional and financial strain the defect causes.  Responsible parents do everything they can to minimize the possibility of birth defects.  Causes such as infections, drugs, alcohol can be controlled.  Parents need to make healthy choices.  Early detection is very important.  Some birth defects can be diagnosed and treated before birth.

G ENETIC C OUNSELING  This involves researching the families complete medical history.  Through research and laboratory testing the counselor can usually tell the couple what genetic problems are present and their risk of passing those problems onto their child- possibly causing a birth defect.  Most people who seek this type of counseling do so because they are aware of a problem that has been passed down through the family.

P RENATAL T ESTS  100’s of birth defects can now be detected before the baby is born.  These tests can alert the doctor to a condition that may be treated before or immediately after birth.  Blood tests may provide this information.  Other tests such as Ultrasound, Amniocentesis, Chorionic villi Sampling can be preformed.  These tests carry a higher risk of danger for baby.

U LTRASOUND  Ultrasound uses sound waves to make a video image of the unborn baby.  This allows the doctor to check for specific health problems. The doctor can:  Tell if the fetus is developing on schedule.  Detect certain defects that involve the skeleton and other organs.  Confirm the due date.  Tell if there is more than one fetus.  This test has become common, and poses no risk for mother or baby.

A MNIOCENTESIS  Amniocentesis involves the process of withdrawing a sample of the amniotic fluid surrounding the baby.  The doctor withdraws the fluid using a needle.  An ultrasound image is used as a guide when inserting the needle.  This test is most often used to test for Down Syndrome.  This test increases the risk for miscarriage.  This test is only preformed when there is strong medical reason.

C HORIONIC V ILLI S AMPLING  Takes a sample of the tissue from the membrane that encases the fetus.  Guided by an ultrasound image, the doctor inserts a tube through the vagina into the uterus. Samples of the uterine tissue are snipped or suctioned off.  This test can be administered earlier in the pregnancy than amniocentesis.  However it carries a higher risk of miscarriage. It also carries a risk of causing birth defects.  Test is administered only after careful consideration.