The Very Beginning

The Very Beginning

The human body begins as one microscopic cell that is formed by fertilization, also known as conception.

FertilizationThe union of a male sperm cell and a female egg cell

The Very Beginning

Within a few days, implantation occurs.

****Need to know the difference between conception and implantation ****

ImplantationThe process by which the zygote attaches to the uterine wall

The Very Beginning

After about two weeks, the zygote becomes an embryo.

EmbryoA cluster of cells that develops between the third and eighth week of pregnancy

The Very Beginning

The embryo is called a fetus after about eight weeks.

Fetus

Group of developing cells

The Growing Embryo

The amniotic sac is a thin, fluid-filled membrane that surrounds and protects the developing embryo.

The umbilical cord is a ropelike structure that connects the fetus with the mother’s placenta.

The placenta is thick, blood-rich tissue that lines the walls of the uterus during pregnancy and nourishes the embryo.

Umbilical Cord

• Serves as a conduit to move oxygen and nutrients from the mother to the growing fetus during pregnancy.

• Takes away waste materials from the developing baby and allows the mother's body to eliminate the waste.

http://www.ehow.com/about_4569487_what-umbilical-cord-attached.html

Multiple Births

In most cases, fertilization results in one embryo.

 

Multiple births- when multiple embryos are formed, Twins, triplets, and quadruplets are the result.

Multiple Births

Identical Twins

Fraternal Twins

Single zygote that splits into two separate embryos.

Identical traits and the same gender.

Two eggs are released and are fertilized by two different sperm.

Can be different genders.

A Healthy Pregnancy

A pregnant woman needs prenatal care to ensure her health and that of her growing baby.

Prenatal care

The steps that a pregnant female can take to provide for her own health and the health of her baby

What to Eat While Pregnant

Calcium helps build bones and teeth, nerves, muscles, and heart.

Protein helps form muscle and other tissue.

Iron makes red blood cells and supplies oxygen to cells.

Vitamin A helps in the growth of cells and bones and in eye development.

Vitamin B complex aids in forming the nervous system.

Folic acid is critical in development of central nervous system.

What to Eat While Pregnant

Females at a healthy weight before becoming pregnant can gain between 25 and 35 pounds during pregnancy.

The Growing Embryo

The Growing Embryo

The Growing Embryo

Avoid Hazards in the Environment

A pregnant female should avoid these common hazardous substances in the environment.

Lead Mercury Smog Radiation

Complications of Pregnancy

The complications of pregnancy can result in

a cesarean delivery, made through an incision in the mother’s abdomen.

premature birth, at least three weeks before the due date.

miscarriage, the spontaneous expulsion of a fetus before the twentieth week of pregnancy.

Complications of Pregnancy

An ectopic pregnancy results when a zygote implants not in the uterus but in the fallopian tube, abdomen, ovary, or cervix.

 

This makes it impossible for the fetus to receive nourishment and grow.

A Healthy Fetus

Expectant mothers should avoid tobacco, alcohol, drugs, and environmental hazards.

An expectant mother should avoid substances that can harm her and her fetus.

Avoid Tobacco Use

Exposure to secondhand smoke increases the risk of having a low-birth-weight baby.

 

Smoking may also affect growth, mental development, and behavior after a child is born.

Avoid Alcohol Use

Fetal alcohol syndrome can cause learning, memory, and attention problems, as well as visual and hearing impairments.

Fetal alcohol syndromeA group of alcohol-related birth defects that includes both physical and mental problems

Avoid Drug Use

Prescription or over-the-counter medications should be used only with the approval of a doctor or other health care professional.

 

In some cases, drug use may lead to the premature birth of the infant, or even a miscarriage.

Childbirth

Birth occurs in three steps.

Step 1: Labor

Step 2: Delivery

Step 3: Afterbirth

Childbirth

Step 1: Labor. Muscle contractions of the uterus become regular, stronger, and closer together.

 

This causes the cervix— the opening to the uterus—to dilate, or widen.

Childbirth

Step 2: Delivery. Once the cervix is fully dilated, the baby passes through the birth canal and emerges from the mother’s body.

 

The baby takes its first breath and cries to clear its lungs of amniotic fluid.

Childbirth

Step 3: Afterbirth. The placenta is still attached to the baby by the umbilical cord.

 

Contractions, although weaker, will continue until the placenta (now called the afterbirth) is pushed from the mother’s body.