Chapter 3 - Genetics, Conception, Fetal Dvlpt, Reproductive Technology Flashcards
T.O.R.C.H. teratogenics
Toxoplasmosis Others (Syphilis, Varicella) Rubella Cytomegalovirus Herpes Varicella
Toxoplasmosis
protozoan parasite found in cat feces + uncooked/rare beef + lamb
- can cause fetal demise, mental retardation, blindness
- avoid cat litter + undercooked beef/lamb
when are fetuses most vulnerable?
first 8 weeks
Cytomegalovirus may cause
- hydrocephaly
- microcephaly
- cerebral calcification
- mental retardation
- hearing loss
Syphilis may cause
- skin, bone, teeth defects
- fetal demise
Herpes varicella may cause
- hypoplasia of hands + feet
- blindness/cataracts
- mental retardations
Rubella may cause
- heart defects
- deafness/blindness
- mental retardation
- fetal demise
Ovarian Cycle
based on maturation of ova
1 follicular phase
2 ovulatory phase
3 luteal phase
follicular phase
start: 1st day of menstruation
end: 12-14 days after
- graafian follicle matures due to LH + FSH
maturing follicle secretes…
estrogen
-causes endometrium to thicken + become more vascular to prep for implantation
ovulatory phase
start: peak of estrogen
end: release of oocyte
- LH peaks 12-36 hr before ovulation
- before peak, estrogen falls + progesterone incr
ovulation
release of oocyte (egg) fr matured graafian follicle
luteal phase
start: after ovulation
end: ~14 days
- follicle> corpus luteum
- secretes high lvl progesterone + low lvl estrogen
corpus luteum
if pregnancy occurs…
vs
if no pregnancy occurs
Prg: keeps secreting E + P until placenta can take over
Not P: corp.lut degenerates> FALL in P> starts the menstruation
Endometrial Cycle
1 proliferative phase
2 secretory phase
3 menstrual phase
proliferative phase
start: after menstruation
end: ovulation
- endometrium gets thicker + more vascular in prep for implantation
- –fr incr level of estrogen
secretory phase
start: ovulation
end: onset of menstruation
- endometrium cont to thicken
- progesterone is secreted by corp.lut
what happens to endometrium when corpus luteum degrades?
tissue degenerates
menstrual phase
sloughing + expulsion of endometrial tissue
ductus venosus
connects umbilical vein to inferior vena cava
-allows for most of oxygenated blood to go directly to right atrium
foramen ovale
connects right + left atrium
- blood in rt atrium is shunted to left atrium
- that way less is going to the lungs and more is going into circulation
- bc lungs are NOT the site of gas exchange
when does foramen ovale close?
- closes after delivery in response to increased blood returning to the left atrium
- takes 3 months to fully seal
ductus arteriosis
connects pulmo artery w descending aorta (which goes to systmc circ)
-most of oxygenated blood is shunted to aorta w small amounts to lungs
when dos ductus arteriosis close?
after birth, it constricts in response to higher blood oxygen levels + prostaglandins
functions of placenta
1 metabolic + gas exchange
2 hormone production
hormones produced by placenta
1 progesterone
2 estrogen
3 hCG
4 hPL
progesterone
- thickens endometrium to facilitate in implantation
- reduces uterine contraction
- reduces GI motility
estrogen
stimulates enlargment of breasts + uterus
hCG
stimulates corpus luteum to continue secreting P + E
-rapidly rises in 1st trimester then rapidly declines
hPL
1 regulates glucose> promotes fetal growth
2 stim breast dvlpt
viruses that can cross placenta
rubella + cytomegalovirus
when does the placenta become fully functional
8th-10th wk
amniotic fluid composition
- mostly water
- macros
- electrolyte
- fetal cell
- lanugo
- vernix caseosa
amniotic fluid production
1st tri: amniotic membrane
2-3rd tri: produced by fetal kidneys
peak amt of amniotic fluid + amt at term
800-1000 mL at 34 wk
-decreases to 500-600 at term
amniotic fluid function
- cushion
- prevents adhesion to membrane
- allows more fetal mvmt> good for muscle/bones
- consistent thermal environment
polyhydramnios
1500-2000 mL
polyhydramnios incr risk for…
- chromosomal disorders
- GI issues
- cardiac
- neural tube
oligohydramnios
less than 500 mL or 50% reduction of norm amount
oligohydramnios is generally r/t
decr in placental functions
oligohydramnios incr risk for…
congenital renal problems
whartons jelly
collagenous product that cushions cord fr compression
infertility for younger than 35
inability to conceive + maintain pregnancy after 12 months of unprotected sex
infertility for older than 35
inability to conceive + maintain pregnancy after 6 months of unprotected sex
rubella tx
vaccine 3 months before getting pregnant or 3 months after labor
