Download PREGNANCY

PREGNANCY
Topics to be covered
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What is pregnancy?
How to detect pregnancy
Fetus formation
Factors affecting fetal growth
Factors affecting gestation
Physical changes during pregnancy
What is pregnancy?
• Pregnancy is the development of an embryo
and subsequently a fetus in the uterus of a
woman for a length of time
• During this stage, physical changes occur to
the woman
• Pregnancy is maintained by hormones (HCG
and Progesterone)
Multiple pregnancy
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A pregnancy with two or more fetuses. Twins - 2 fetuses, Triplets - 3 fetuses,
Quadruplets - 4 fetuses, Quintuplets - 5 fetuses, Sextuplets - 6 fetuses and
Septuplets - 7 fetuses
Naturally occurring factors causing multiple pregnancy are:
i.
heredity
- A family history of multiple pregnancy increases the chances of having
twins
ii.
older age
- Women over 30 have a greater chance of multiple conception.
iii.
high parity
-Having one or more previous pregnancies, especially a multiple pregnancy,
increases the chances of having multiples.
iv.
race
-African-American women are more likely to have twins than any other race.
Asian and Native Americans have the lowest twinning rates. Caucasian
women, especially those over age 35, have the highest rate of higher-order
multiple births (triplets or more).
How to detect pregnancy?
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Urine test – detect hCG
Blood test – detect hCG
Ultrasound
Milk test – P4 (animals)
Blood test – PMSG (animals)
Urine test
•The hCG Urine Pregnancy Test
Strip is a test kit based on a
visual, qualitative principle for the
determination of Human Chorionic
Gonadotropin (a glycoprotein
hormone
secreted
by
the
developing
placenta
after
fertilization) in urine specimens.
• Pregnancy Test Strips are over
99% accurate and are capable of
detecting 20mIU/ml/hCG. Can
test accurately 6 to 8 days after
conceiving - and 7 days after
missed period.
•Appearance of hCG soon after
conception and its subsequent
rise in concentration during early
gestational growth make it an
excellent marker for the early
detection of pregnancy
hCG (Human Chorionic Gonadotrophin)
• The developing placenta begins releasing hCG into blood as early as 6
days after implantation. Some hCG also gets passed in the urine
• HCG helps to maintain pregnancy and affects the development of fetus
• Levels of hCG increase steadily in the first 14 to 16 weeks following LMP,
peak around the 14th week following LMP, and then decrease gradually
• The amount that hCG increases early in pregnancy can give information
about pregnancy and the health of the baby. Shortly after delivery, hCG
can no longer be found in the blood
• More hCG is released in a multiple pregnancy, such as twins or triplets,
than in a single pregnancy
• Less hCG is released if the fertilized egg implants in a place other than
the uterus, such as in a fallopian tube. This is called an ectopic
pregnancy.
Ultrasound
•An ultrasound test is a radiology
technique, which uses high- frequency
sound waves to produce images of the
organs and structures of the body. It
involve no radiation and studies have
not revealed any adverse effects.
•The sound waves are sent through
body tissues with a device called a
transducer placed directly on top of the
skin, which has a gel applied to the
surface.
•The sound waves that are sent by the
transducer through the body are then
reflected by internal structures as
"echoes." which return to the
transducer and are transmitted
electrically onto a viewing monitor.
Ultrasound pictures
Week 5
Twins
Week 8
Twins kicking
Week 11
Fetus formation
• Gene dependant
• Size dependant on nutrition and health of mother,
parity (primiparous mothers have small babies as
compared to multiparous mothers), mother’s size,
pregnant more than one baby and self-damage
caused by smoking, drug addiction, alcoholism etc
• Small sized baby is due to prematurity or even if fullterm, there must be a factor to cause a retarded
growth for the baby
Fetal Development
• Heart and brain develop from 3rd week
• Heart starts to pump blood from week 4-5
• Feet and hands starts to develop and tail at coccxy starts to
shrink
• Embryo is less than an inch long at week 5
• Hands and feet is visible and nose also starts to form
• At week eight, it is about an inch long
• By week 9, embryo is called a fetus
• Sexual organs starts to form but sex is not yet determine
• Other organs also starts to form and develop until birth
• Rate of fetal growth is slow until week 20 but
accelerate to a maximum at week 30-36
• Peak of growth velocity is on week 8
• Fetal nutrition is from CHO (glucose), amino
acids and lactate. Fatty acids, vitamins and
minerals are also transferred to the fetus via
the placenta
Factors affecting fetal growth
• Genetic (species, breed, genotype)
• Environmental (nutrition, size, parity, size and
blood circulation of placenta)
• Fetal hormones (thyroid, growth hormone,
somatomedins)
• Gestation length: 280 days or 40 weeks or 9
months and 10 days
• LMP – Last Menstrual Period
• EDD – Estimated Delivery Date (First day of
last menstrual period plus 280 days)
• Trimester – 3 months
• Human – 3 trimesters
• LMP – 31/1/2009
• Menstrual cycle – 28 days
• Add 40 weeks or 9 months and 10 days (280
days)
• EDD – 7/11/2009 (An estimation!)
Factors affecting gestation length
• Maternal factor – age of mother
• Fetal factor – number of fetuses, gender,
adrenal and pituitary function
• Genetic – species, breed, fetal genotype
• Environmental factors – nutrition,
temperature, season
Physical changes during pregnancy
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No menstruation
Nausea in first trimester
Back and hip pains
Increase in body weight
Pigmentation of skin especially in fair-skinned women
(cholasma – mask of pregnancy) especially at the facial
region
‘Quickening’ or baby movements in uterus – occurs at 5
months pregnancy onwards
‘Braxton-Hicks contraction at 6-7 months pregnancy
‘Engagement’ at 8 months pregnancy
Others eg pica (Pica is a pattern of eating non-food
materials such as dirt or paper and should last at least 1
month to fit the diagnosis of pica.)
Back and hip pains
Mask of pregnancy
Development of embryo and fetus
Abnormal pregnancies – Ectopic pregnancy
• Occurs when a fertilized egg attaches somewhere other
than in the uterus, usually in a fallopian tube (tubal
pregnancy).
• Because an ectopic pregnancy can cause life-threatening
complications, the pregnancy must be ended with
medicine or surgery.
• An ectopic pregnancy, especially a tubal pregnancy, can be
dangerous because the fallopian tube does not stretch as
the fertilized egg grows. If a tubal pregnancy is not
detected and treated early, the tube may burst. This can
be a life-threatening situation and requires emergency
surgery.
• Pelvic inflammatory disease or tubal surgery increases the
risk of having an ectopic or tubal pregnancy by creating
scar tissue that may block the fallopian tube.
Abnormal pregnancies – Molar pregnancy
• A mass of abnormal tissue (hydatidiform mole)
that comes from the placenta inside the uterus,
which triggers symptoms of pregnancy. About 1 :
1,000 women with early pregnancy symptoms has
a molar pregnancy. Two types of molar pregnancy:
complete and partial.
• Complete molar pregnancy. In place of a normal
placenta/embryo, the hydatidiform mole is
abnormal placental tissue that grows into a
grapelike cluster that can fill the uterus.
• Partial molar pregnancy. The placenta grows
abnormally into molar tissue. Any fetal tissue that
develops is likely to have severe defects.