DMIS 1100 class 8
lecture on 10/27/10
What are the 4 positions of the uterus?
anteverted, anteflexed, retroverted, retroflexed
At what point in a pregnancy would a retroverted uterus become anteverted?
With every 100 ovums, how many will be lost?
Out of 100 ovums how many are lost due to no fertilization?
Out of 100 ovums how many are lost due to fertilization but no implantation?
Out of 100 ovums how many are lost due to the fertilized egg aborting at the onset of meses?
What is the length of pregnancy (support of pregnancy)?
280 days (40 weeks)
What is the normal full term gestational age?
When does gestational age begin?
14 days prior to conception (first day of LMP)
When can a spontaneous abortion occur?
between 5-12 weeks
How many eggs are infant girls born with?
What is LMP?
last menstrual period
What happens on day 1 of the gestation period?
pituitary gland releases FSH, ovary creates egg and follicle growth begins
What happens during days 2-7 of the gestation period?
follicle grows and produces estrogen which stimulates the lining of the uterus to produce new blood vessels
What happens during days 7-12 of the gestation period?
follicle grows to maturity (graafian follicle 18-24 mm)
What happens on day 14 of the gestation period?
estrogen peaks which causes pituitary gland to release LH which then causes graffian follicle to rupture & release ovum
What is a zygote?
What is the rate of growth of the primary ovum between days 1-14 of the gestation period?
What happens on day 14-15 of the gestation period?
the released graafian follicle is transformed into a corpus luteum cyst which produces progesterone, the progesterone prepares the uterus for implantation of a fertilized egg
What two hormones peak at ovulation?
LH and estrogen
What hormone is released from the endometrium?
What two structures release estrogen?
graafian follicle & endometrium
What are the two hormones that the pituitary gland releases during the gestation period?
FSH & LH
What can be given intravenously to a woman to stimulate ovulation if LH is low?
How can a woman determine that she is ovulating?
body temp at highest level (1/2%-1% higher than normal)
What can be given vaginally to a woman to support implantation if progesterone is low?
What happens if no fertilization occurs by day 21 of the gestation period?
estrogen & progesterone levels drop, endometrium outrgrows the blood supply and begins to slough off
In which part of the fallopian tube is it most common for fertilization of the ovum to take place?
ampulla (distal third of the tube)
During day 16-17 of the gestation period what is the fertlized egg referred to as?
How many cells make up a morulla?
What occurs on day 20-21 of the gestation period?
At the time of implantation, what does the developing placenta release?
What two hormones does the corpus luteum continue to secrete after implantation?
estrogen & progesterone
What occurs on days 28-33 of the gestation period?
the gestational sac develops with the chorionic villi and attaches to the urerine wall to form placenta, inner cell mass forms as the embryonic disk and primary yolk sac
What is the outer layer of a blastocyst?
What is the cluster of cells within a blastocyst?
inner cell mass (embryo)
What does the trophoblast release?
By day 35 of the gestation period (5 weeks mestrual age) what can be seen within the uterus?
double sac sign or psuedosac
What is the double sac sign?
2 layers of cells appear as a double sac
What does a pseudosac indicate?
What may be able to be seen within the gestational sac at day 35?
yolk sac and/or fetal pole
At 5 weeks gestation (day 35) what has developed within the embryo?
neuro plate, lung buds
Lung buds continue to grow until when?
17 weeks gestation
What is IUP?
At what age is a gestation sac that measures 10 mm?
5 weeks gestation
How is gestation age in days determined?
(x¹+x²+x³) + 30 / 7.7
How is gestation age in weeks determined?
x¹+x²+x³ / 3 AND use look up table for gestational age
Why is the measurement of the gestation sac not accurate for gestation age?
can be off by 2 weeks dependent on measurements & irregularity of sac
At week 6 gestation what has formed within the embryo?
forbrain/midbrain/hindbrain from brain, spine and cord/secondary yolk and sac/heart rate from neurotube
At 6 weeks gestation, what measurement can be taken?
What is CRL?
crown rump length (head to butt)
Why is CRL the most accurate fetal measurement?
it is age accurate within 4 days
What should be seen on ultrasound for a 6 week old fetus (especially with transvaginal exam)?
When MUST a heart rate be seen on transabdominal scan?
7 weeks gestation
The CRL should meausure what for a fetus that is 6-6.5 weeks old?
What is the age of a 1 cm embryo?
7 weeks gestation
At 7 weeks gestation, what can be seen on ultrasound?
shape of embryo head and body
When are fetal arm buds first visualized on ultrasound?
8-9 weeks gestation
At what age gestation does spine mineralization occur?
At what age (gestational) does an embryo progress to be a fetus?
At what age has the fetal organs and systems developed and have been correctly positioned?
10 weeks gestation
At 10 weeks gestation, how does the brain appear?
What cellular and aembryonic architecture occur at 10 weeks gestation?
neurocranial axia, cardiovascular system, gastrointestinal system, urogenital system, primitive skeleton, muscles, cord herination, kidney tissue
Most body systems can be visualized on ultrasound by what age?
9-12 weeks gestation
What abdominal wall defect can result from fetal bowel protruding from the abdominal wall through the cord site after 13 weeks gestation?
What type of twins originated from 2 eggs, 2 sperm, and develop in 2 seperate sacs and share 1 placenta?
What type of twins originated from 2 eggs, 2 sperm, and develop in 2 seperate sacs, each with their own placenta?
What type of twins originate from 1 egg, 1 sperm, and develop within the same sac, and share 1 placenta?
What type of twins originate from 1 egg, 1 sperm, and develop in seperate sacs, and share 1 placenta?
What produces cerebral spinal fluid in the fetus?
What can be seen on ultrasound in a 12 week gestation fetus?
choroid plexus, fetal skull, femur
What is BPD? (fetal meausurement)
What is AC? (fetal meausurement)
When does fetal intestinal activity begin?
11 weeks gestation
When does fetal swallowing begin to occur?
12 weeks gestation
What measurement can be taken at 12 weeks gestation?
BPD and femur length
What would indicate that a transvaginal ultrasound should be performed within the first trimester?
vaginal bleeding, pain, abdomen measures large or small for dates, dates are unknown, drug abuse, IUD, trauma, history of twins or miscarriage
Why may there be vaginal bleeding in the first trimester?
ectopic pregnancy, miscarriage, hydatiform mole, choriocaricnoma
Why would a woman measure larger than usual during her pregnancy?
if there is a mass, mulitiple fetus, incorrect dates
Why would a woman measure smaller than usual during her pregnancy?
fetal demise, ectopic pregnancy, incorrect dates
Why do correct dates need to be determined during pregnancy?
so test dates can be determined, if cesarian section is needed, EDC
Why is it important to know if a woman has abused drugs during her pregnacy?
it can cause fetal anomalies, growth rate changes
What weeks are within the 1st trimester?
0-12 weeks gestation
What weeks are within the 2nd trimester?
13-24 weeks gestation
What weeks are within the 3rd trimester?
25-40 weeks gestation
What is EDC?
estimated date of confinement