Conception and Prenatal
Development
What do you already know about
conception?
Let’s discuss before you begin
worksheet!
Anatomy
Female sex cell called __________.
 Male sex cell called __________.
 Ovum is released by the ___________.
 Ovum travels down the ______________
tube.
 Sperm travels through the vagina, cervix,
up the ___________ to the ___________
where it could ____________ the ovum.

Reproductive Systems
Male reproductive system
 Female Reproductive System

Movie time…
Process of Conception Video
 http://video.google.com/videoplay?docid=
-4530276804858686422 –

Conception
When the ovum (egg) and sperm unite in
the fallopian tube; pregnancy begins.
 Fertilization can take place only 2-3 days
after the ovum is released into the fallopian
tube.
 Sperm can live for up to seven days.
 Only about 10 days a month can a woman
can become pregnant.

Contraception

A method used to avoid pregnancy
– Abstinence
– Permanent
– Chemical/hormonal methods
– Barrier methods
– Rhythm method
 Most
do not protect against STD/STI
Other forms of fertilization
(for Infertility)

Artificial insemination
– Sperm are injected with a special needle into
the uterus. May be from donor or natural
father.

In Vitro fertilization
– Fertilization occurs outside of uterus and zygote
are implanted in uterus.
– Ovum transfer – egg taken from donor

Surrogate mother
– Become pregnant for another couple
Three stages of baby’s
development
Zygote/Germinal
Embryonic
Fetal
Zygote/Germinal Stage
Lasts about two weeks, when cells
duplicate and form into a mass of cells.
 Zygote travels down the fallopian tube to
the uterus. The uterine lining thickens to
receive the zygote.
 After two weeks the zygote is the size of a
pinhead.

Embryo Stage
 3rd
– 8th week of development
 Mass of cells develops into all the major
systems of the human body.
– All organs are present, but not
functioning.
– Brain begins to take control of organs.
– Drugs, alcohol are dangerous.
 Sac w/ amniotic fluid begins to surround
embryo for protection. http://www.babycenter.com/2_insidepregnancy-weeks-1-to-9_10302602.bc
Embryonic Period
Placenta (tissue in the uterus that is rich
in blood cells) develops.
 Umbilical cord between baby and mother
carries food and oxygen to baby from
mother’s blood stream, and takes away
waste products.

Fetal Alcohol Syndrome (FAS)
Baby has smaller head and size for
gestational age; thin arms & legs.
 Flat mid-face and nose bridge; ear and hand
anomalies; skin folds on corners of eyes.
 Thin lips; small lower jaw.
 Non-visible injuries:

– Central nervous system problems.
– Learning disabilities
– Emotional and behavioral disorders; hyperactivity
– Reduced cognitive ability
video
http://abcnews.go.com/GMA/video/adopti
ve-parents-give-child-awat-fasd11734589&tab=9482930&section=120685
2&playlist=11128107
 Video of parents who had to give away
daughter.

Alcohol statistics






Among pregnant women, 1 in 10 drink alcohol.
Among pregnant women, 1 in 25 binge drink.
More than 1 in 5 women drink in first
trimester.
About 1 in 100 babies are born effected by
alcohol exposure. About 1 in 1000 have FAS.
Lifetime expense of baby with FAS is approx.
$2m
After birth, can still be affected through breast
feeding.*
How drugs affect the Unborn

Three ways:
– Direct injury – leading to birth defects or
death
– Constriction of blood vessels in the placenta,
reduces oxygen supply & nutrients to fetus,
resulting in low birth weight and/or premature
birth.
– Forceful premature contractions of uterine
muscles, reducing blood supply. May trigger
premature birth or preterm labor.
Life time effects

Up to 2 years:
– Feeding, Cerebral Palsy, irritability, poor
weight gain, tremors, vision problems…

Toddler to preschool:
– Social interaction, delayed language develop.,
processing information, hyperactivity…

Early school – Teenage years:
– Behavioral problems, learning disabilities,
neglect and abuse.
Drug Exposure
More than 90% of pregnant women take
or use some type of drug.
 Between 550,000 – 750,000 infants have
been exposed to drugs.
 2 – 3 % of birth defects are a result of
prenatal drug exposure.
 No drug should be used without Dr.
supervision.

Fetal Stage
 8th
week – birth
 “Flutter” about 4th-5th month – feeling of
first kick.
 “Quickening” when kicks become more
frequent and stronger.
 7th month baby can live outside of womb
but will need medical care.
Fetal Stage
 8th
-9th month
– Organs begin to be ready to function
– Moves into head down position
– Amniotic fluid decreases
– Weight gain continues
– Fetus gains fat cells to protect it and
keep it warm; Baby’s skin becomes
smoother as it fills in.
Preparing for birth
“Lightening” when baby’s weight shifts
down into position. Days to weeks before
labor begins.
 Should be head down.
 Child will be born 37-42 weeks after
conception.

Chromosomes

Chromosomes contains genetic materials
that determine who you are hereditarily
46 total – 23 from egg/ 23 from sperm
 Dominant genes – stronger gene;
characteristics are prominent
 Recessive genes – weaker gene; characteristic is
“carried” but may not be seen.
 Sex chromosomes – XX is girl/ XY is boy

Birth Defects
Hereditary or environmental causes
 Physical or mental
 May spontaneously abort – miscarriage
 May have still birth – death of developing
baby after 20 weeks
 Genetic counseling and prenatal testing to
have knowledge of defect and how to live
with it.

Diseases that can cause defects
Rubella
(German Measles)
Blindness, deafness, heart
disease, mental delays
Vaccine before getting
pregnant
Toxoplasmosis
Blindness, learning
disablities, miscarriage,
stillbirth
Do not clean cat litter; eat
uncooked meat;
contaminated produce
Chicken Pox
Skin scarring, limb defects,
eye problems,
abnormalities, miscarriage.
Vaccine before becoming
pregnant
STDs & AIDS
Physical & mental
disabilities; death
Discuss exposure w/ doctor;
get tested; take precautions
Prenatal testing
Prenatal test
Description
Risk
Alpha-fetoprotein
(AFP)
(15 – 20 weeks)
Blood test
No risk to date.
Ultrasound
(20th week)
Sound Waves used
to make image of
fetus.
No risk to date
Amniocentesis
(16th week)
Withdraw amniotic
fluid to determine
defects
Miscarriage
Chorionic villi
sampling (CVS)
(6-10 wks)
Take sample of
tissue from
placenta
10 weeks
Miscarriage
http://www.babycenter.com/2_inside
-pregnancy-labor-andbirth_3658872.bc