Pregnancy and Parenthood

Pregnancy and Childbirth

April 4, 2011

Vocabulary1. Gametes [Sperm (male) and egg (female)]

• Each gamete only has half the DNA needed to create a new human being

2. Fertilized egg/zygote • Zygote = the first cell of a new person, formed at

fertilization3. Blastocyst

• Blastocyst = a hollow ball of 64-128 cells that attaches to the uterine wall

4. Embryo• Embryo = the developing infant during the first two

months of conception

Becoming pregnant A woman can become pregnant from sexual intercourse

with a man It takes TWO PEOPLE to become pregnant

The male gamete (sperm) travels through the fallopian tubes of the woman, where it meets a female gamete (egg) and fertilizes it. Each gamete contains half the DNA necessary for a new

human being. After 24-30 hours, the two gametes will combine (the sperm

enters the egg, fertilizing it). Once the egg is fertilized, it is called a zygote.

A zygote contains all the DNA necessary for a new human being.

After fertilization After being fertilized, the zygote begins to replicate…

From 1 to 2 cells (a day and a half) From 2 to 4 cells (two days) From 4 to 8 cells (two and a half days) From 8 to 16 to 32 cells (three days)

By the fourth day after fertilization, the zygote becomes a hollow ball of 64-128 cells called a blastocyst.

On the 6-7th day, the blastocyst attached to the uterine wall

By the 11-12th day, the blastocyst is called an embryo, and has implanted itself into the uterus. Now, we say the woman has become pregnant.

After fertilization

Very early pregnancy Once the embryo is implanted into the uterus, it

starts to change things…Secretes a hormone called HCG into the mother’s

blood.This hormone stops the menstrual cycle and allows the

pregnancy to continue by increasing the levels of estrogen and progesterone.

HCG also causes nausea and vomiting (morning sickness), enlarged breasts, more frequent urination, fatigue, and growth of the uterus.

If a woman uses a “home pregnancy test”, it is looking for HCG in her urine.

Dangers of early pregnancy Early pregnancy is usually a very safe time – many

women do not even realize they have become pregnant. Rarely, however, the embryo may implant in the wrong

place – outside of the uterus. Usually this occurs when the embryo implants on the

fallopian tube, and is called a tubal pregnancy. If this happens, the embryo will soon become too large for the

space, and the tube will burst. This causes internal bleeding and requires immediate medical

help. Seeing a doctor when you become pregnant can make sure that

your pregnancy is normal and healthy.

Development of the fetus Fetus is the the infant during pregnancy. The body of the fetus is usually formed

completely by ten weeks.During the rest of the pregnancy, the fetus grows

larger, and develops functioning organs. Before birth, the fetus receives energy and

nutrients from the mother through the placenta and umbilical cord.

By birth, the fetus usually weighs around seven pounds.

Development of the fetus – how?? The fetus lives within a fluid-filled sac called the

amnion The fluid is called amniotic fluid. The fluid protects the fetus from the other parts of the

mother’s body, and is a cushion. When a woman’s “water breaks”, just before birth, this is

the fluid that is released.o Within the uterus, an organ called the placenta develops during pregnancy.• This secretes hormones to direct pregnancy, and transfers things between mother and fetus • Mother fetus (oxygen, nutrients, energy) • Fetus mother (carbon dioxide, waste)

What happens to the mother? There are obvious and hidden changes to the

mother’s body during pregnancy. Many changes help provide more energy:

Her heart beats faster, she grows more blood cells, and breaths more.

Many changes make room for the fetus:The uterus more than triples in size.Other organs move out of the way to make room – one

of the reasons why a pregnant woman needs the bathroom more often!

Staying healthy during pregnancy Healthy behaviors are especially important

during pregnancy because they ensure that the fetus will grow healthily.NutritionHealthy weight gain (28-30 pounds)Physical activityManaging stressPrenatal care

HOMEWORK FOR TUESDAYHow can a woman avoid becoming pregnant?

What are some steps that can be taken if a woman is not ready to have a baby?Half-page essay, Due TuesdayUse your book! And your notes!!

Risks during pregnancy The mother controls what is in the fetus’

environment – what is around the fetus. Health risks taken by the mother during

pregnancy often put the fetus at risk:Drug use – many drugs (legal and illegal) can harm

the fetus. A doctor should approve any medicine taken.

Alcohol useCigarette use

Drinking alcohol during pregnancy Drinking alcohol while pregnant is very

dangerous to the fetus, because the fetus is too small to handle any alcohol in the blood.

If alcohol is consumed too much or too often, the fetus may develop fetal alcohol syndrome (FAS).Causes growth retardation, facial malformations, and

nervous system problems (such as mental retardation and behavioral problems).

Smoking cigarettes during pregnancy Smoking during pregnancy increases the risks

of almost every problem for the fetus. Smoking reduces the amount of oxygen that

reaches the fetus, and exposes the fetus to harmful chemicals.

Birth defects and life-long health problems can occur in a fetus when the mother smokes during pregnancy.

Childbirth Childbirth has a lot of cultural tradition

It is most important that a woman feel confident and ready to have a child.

Stages of labor – actually giving birth1. Early labor – the fetus becomes positioned for

birth2. Contractions and dilation of the cervix to about 10

centimeters across3. Infant descends through the birth canal4. Delivery of the placenta (afterbirth)

Very culture-rich part of childbirth

Complications of pregnancy Ectopic pregnancy

The fetus develops outside of the uterus, such as in a fallopian tube, damaging the mother’s internal organs.

Eclampsia High blood pressure during pregnancy, may cause seizures

and other complications. Gestational diabetes

A form of diabetes that may occur during pregnancy Increases the risk of diabetes later in life for mother and

child.

Complications of childbirth Breech birth

The fetus is upside down, and not head-first. Occurs in 5% of pregnancies.

Prolapsed cord This occurs when the umbilical cord leaves the birth canal

before the fetus. The cord will be pinched by the fetus and oxygen to the fetus

will be cut off. Pre-term or post-term birth

Infants born premature need extra care and medical assistance to survive.

Infants born later than 40 weeks may cause the mother medical complications and difficult labor.

Hemorrhage Uncontrollable bleeding following labor.

Alternative birthing methods If natural birth is not occurring as is should,

there are other ways of removing the infant from the mother’s body:Epistiotomy – a doctor will cut from the vagina

towards the anus to enlarge the birth opening (many risks and complications)

Cesarean birth – a doctor will surgically remove the baby from an incision in the woman’s abdomen (many risks and a longer healing time for the mother)

After the birth After giving birth, the mother slowly returns

to her pre-pregnancy bodyLose the increased fluids and uterine sizeHormones return to normal levels

During this transition, some women may experience a form of depression called post-partum depression.Related to the hormonal changes after birth, and

to the life-changes related to having a baby

After the birth Breastfeeding is a very healthy and important activity

for new infants and mothers. Immediately after birth, the mother will produce

colostrum, which is made before breastmilk and contains: Important nutrients to keep the new baby healthy Antibodies to keep the baby safe from infection

Breastfeeding also triggers hormones that help the mother return to full health

VOCABULARY YOU SHOULD KNOW FROM THIS LECTURE Gamete Fertilize Zygote Blastocyst Embryo HCG Tubal pregnancy Fetus Amnion

Amniotic fluid Placenta Fetal alcohol syndrome Epistiotomy Cesarean section Post-partum depression Colostrum