THURSDAY, APRIL 20, 2017
What are we doing?
Prenatal Development
Why are we doing it?
Students will understand how babies develop.
How does it fit in with what we have previously
done?
THE REPRODUCTIVE
SYSTEM
A Practical Guide
Unlike other animals, humans can
MENSTRUATION
P H A SE S O F M E N ST R U A L C YC L E
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The day count for menstrual cycle begins on the first day of menstruation when blood starts to come out of the vagina. In this section, the length of menstrual cycle has been assumed to be 28 days (which is the average among women). The entire duration of aMenstrual cycle can be divided into four main phases:
-Menstrual phase (From day 1 to 5) -Follicular phase (From day 1 to 13) -Ovulation phase (Day 14)
M E N ST R U A L P H A SE – D A Y 1 T O 5
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Menstrual phase (day 1-5)Menstrual phase begins on the first day of menstruation and lasts till the 5th day of the menstrual cycle. The following events occur during this phase:
The uterus sheds its inner lining of soft tissue and blood vessels which exits the body from the vagina in the form of menstrual fluid. Blood loss of 10 ml to 80 ml is considered normal.
F O L L IC U L A R P H A SE (D A Y 1 -1 3)
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This phase also begins on the first day of menstruation, but it lasts till the 13th day of the menstrual cycle. The following events occur during this phase:O V U L A T IO N P H A SE (D A Y 1 4)
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On the 14th day of the cycle, the pituitary gland secretes a hormone that causes the ovary to release the matured egg cell. The released egg cell is swept into the fallopian tube by the cilia of the fimbriae.LU T E A L P H A SE (D A Y 1 5-2 8)
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This phase begins on the 15th day and lasts till the end of the cycle. The following events occur during this phase:-The egg cell
released during the ovulation phase stays in the fallopian tube for 24 hours. -If a sperm cell does not impregnate the egg cell within that time, the egg cell disintegrates. -The hormone that causes the uterus to retain its
FERTILIZATION normally occurs in the Fallopian Tubes
An egg is
usually a few
days old
before it
implants in the
uterus. At this
point, it has
already
divided
FERTILIZATION & PREGNANCY
Sperm must travel to the egg and penetrate to
combine the DNA from both parents -- this creates the first cell after fertilization: the ZYGOTE
CONCEPTION
Refers to the point at which the egg is fertilized
*Some believe life begins at conception*
Conception can also be a verb.
Jane did not have trouble conceiving her first child.
Bob could not conceive of a situation where he would need a parachute.
IF THE ZYGOTE HAS THE
INCORRECT NUMBER OF
CHROMOSOMES, IT MAY NEVER
START GROWING. AN EXTRA
CHROMOSOME #21 WILL RESULT IN
THE BABY HAVING DOWN
How does a woman know she is pregnant?
●
Missed period
●
Changes in body,
tenderness in
breasts, nausea…
etc
●
Pregnancy test –
tests urine for
At the 8th week, the embryo is called a FETUS
At 8 weeks
http://www.flickr.com/photos/lunarcaustic/3385925240/
What Causes Morning Sickness? It is likely hormones that rise
rapidly with most incidences occurring in the first trimester Human chorionic gonadotropin (hCG): This hormone rises rapidly during early pregnancy. No one knows how hCG contributes to nausea, but it's a prime suspect because the timing is right:
Nausea tends to peak around the same time as levels of hCG.
What's more, conditions in which women have higher levels of hCG, such as carrying multiples, are
FETAL TESTS
Amniocentesis & Chorionic Villi Sampling
AMNIOCENTESIS
Recommended by doctor after an abnormal “Triple Test”. Detects genetic disorders in the baby.
Collects sample of amniotic fluid.
Can detect chromosomal abnormalities (Down’s), neural
tube defects (spina bifida) and genetic disorders (cystic fibrosis).
Triple test – does not diagnose a problem, only signals
that there may be an abnormality and further testing is needed.
AFP – protein produced by fetus.
hCG – protein produced within the placenta.
CHORIONIC VILLI SAMPLING
Diagnostic test for chromosome abnormalities
and genetic disorders.
Family history.
Collects larger samples than amniocentesis with
faster test results.
Chosen over amniocentesis because can be done
earlier in pregnancy.
Tests for chromosomal abnormalities and genetic
LABOR
Contractions of muscles occur and become
faster and faster, this timing can be used to predict the
progression of the labor. Braxton Hicks contractions can occur throughout pregnancy, but probably more
frequent at the end
An epidural can be used to manage pain of labor. A shot in the spine will temporarily eliminate any feeling below that point. Mom is awake for the birth, but doesn't have the pain of it.
Babies aren’t so cute when
they’re born – it’s a rough road to leave the womb
Some women opt to give birth in water.
This woman was waiting on the midwife and delivered when her husband went to answer the door.
