Term
| how often dows twinning occur |
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Definition
CONSTANT fraction 1/250
1/90 births(less born due to vanishing twin syndrme) |
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Term
| what is the biggest problem with more fetuses in the uterus |
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Definition
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Term
| why have multifetal gestations been increasing |
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Definition
| assisted replication and fertility agents |
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Term
| what are factors that influence changes of dizygotic twinning 6 |
|
Definition
race: black > white > asian
increased age
family hx
increasing parity
ovulation induction
super ovulators |
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Term
| what are the two instances where multifetal gestations occur, which is most common |
|
Definition
splitting of zygote into two or more embryos making MONOZYGOTIC (IDENTICAL) twins
more than one ovum is fettilized by two seperate sperm (more common) causing DIZYGOTIC (FRATERNAL) twins. this is all boy/girl twins |
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Term
| how are dichorionic diamniotic twins made |
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Definition
split zygote in 0-3d, each embryp has 2 chorion and 2 amnion
(can be monozygotic or dizygotic) |
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Term
| how are monochorionic-diamniotic twins made |
|
Definition
split zygote in 3-8d
1 chorion, 2 amnion |
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Term
| how are monochorionic-monoamniotic twins made |
|
Definition
split zygote in 8-14d
after day 8 amnion is completely differentiated
1 chorion, 1 amniona |
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Term
| how are conjoined twins made |
|
Definition
splut after 14d
fetal cells have already irreversibly differentiated and division may be incomplete |
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Term
| what is the incidence of the 4 different types of twinning, which has the highest rate of fetal loss and complications |
|
Definition
dichorionic-diamniotic 20-30%, 2/3 of twins
monochorionic-diamniotic 70-80%, 1/3 of twins
monochroionic-monoamniotic 1% of twins, most dangerous
conjoined 1/70,000 |
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Term
| how does CO, vascular resistance, renal flow change in pregnancy with twins |
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Definition
CO increases by 40-50% in antepartum in normal birth and 70% with twins
vascular resistance is not influenced by twins
renal plasma flow is increased in twins over singletons |
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Term
| what can a fundus >4cm past date mean 5 |
|
Definition
inaccurate gestation age
multiple gestation
hydramnios
gestational trophoblastic disease
pelvic tumor/fibroids |
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Term
| how is a multifetal gestation diagnosed 3 |
|
Definition
fundus >4cm past date
ultrasound
elevated MSAFP |
|
|
Term
| what causes elevated MSAFP 3 |
|
Definition
twins
down syndrome
spinibifidia |
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Term
| what are the morbidities of twins 8 |
|
Definition
small for gestational age
preterm labor
anemia
antipartum hemorrhage
IUFG >20wks: greater risk of fetal demise
congenital malformations
hyperemesis graviderium
PIH (gestational HTN) - more in dizygotic |
|
|
Term
| what is hyperemesis graviderium |
|
Definition
| too much gut growth beyond 1st trimester |
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|
Term
| explain the deviations in fetal weight in twins |
|
Definition
babies grow at same rate in 1st/2nd trimesters as if there was one baby
at 26-28 wk growth slows |
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Term
| explain what twin-twin transfusions syndrome is |
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Definition
| in monochorionic gestations there are not two placentas so babies share blood from mom and there is vascular anastamosis so one baby gets more blood |
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|
Term
| what are the 3 types of twin-twin transfusions, which is most serious |
|
Definition
artery-artery - serious
vein - vein
artery - vein |
|
|
Term
| what are signs of twin-twin transfusion in recipient twin 5 |
|
Definition
hypervolemia, ascites, pleural effusion, pericardial effusion
tries to eliminate excess volume and polyuria causing polyhydramnios (too much amniotic fluid) |
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|
Term
| what are the signs ot twin-twin transfusion in donor twin 3 |
|
Definition
| IUGR, oligohydramnios, hypovolemia |
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Term
| how is twin-twin transfusion tx 2 |
|
Definition
theraputic amniocentesis: remove fluid from recipient sac towards normal
intrauterina laser ablation of anastamoses |
|
|
Term
| prognosis of twin-twin transfusion 2 |
|
Definition
untreated: 100% mortality due to premature membrane rupture and preterm labor
earlier in gestation is worse and more agressive |
|
|
Term
| what are the outcomes in mild forms of twin-twin transfusions |
|
Definition
difference iin weight by 20%
difference in Hb
discordnate growth |
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|
Term
| what is discordant growth |
|
Definition
difference in weight divided by weight of larger getus is 20% or more
asi 20 mm differencein abdominal circumference, 5% mean circumference or 5mm in biparietal diameter |
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Term
| what is the chance labor will be preterm in twins, triplets, and quadruplets |
|
Definition
40% twins
70% triplets
90% quads |
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|
Term
| 6 ways to manage multi fetal gestation |
|
Definition
nutrition: balanced diet, increase calories, multivitamin, minerals
increased blood loss at delivery: prevent anemia (Fe)
fetal growth: increase rest at 24-26 wjs
preterm labor: educate on signs of labor, cervical exam every 1-2 wks
pregnancy induced HTN: frequent BP checks and urine protein leaks
fetal growth/discordinate growth: periodic ultrasounds |
|
|
Term
| what is the ultrasound for multifetal gestation, what is it checking for |
|
Definition
every 4 weeks after 20 wks
AFI: amniotic fluid indexes
growth |
|
|
Term
| how can we monitor for pre-term labor 2 |
|
Definition
fFN (fetal fibronectin) should be asent, can indicate preterm labor (50/50 is positive)
cervical length checks by ultrasound: shortening can indicate preterm labor |
|
|
Term
| how can we prepare for preterm labor with drugs |
|
Definition
| steroids B-methazone and dexamethasone increase fetal lung maturity |
|
|
Term
| what are the presentations of multifetal birth, which need surgery |
|
Definition
vertex/vertex
vertex/breech
breech/vertex: need C section
triplets and quads always C section
ALWAYS PREPARE FOR C SECTION IN MULTIPLE GESTATION |
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|
Term
| why should you always prepare for a C section in multiple gestation 2 |
|
Definition
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|
Term
| hemorrhage is more frequent in multifetal gestation, how can you stop it 5 |
|
Definition
massage uterus to help it clamp down and control bleeding
oxytocin: helps uterus contract
ergotamine/methergine: contracts uterus
hemabate/prostaglandin: contracts but gives mom diarrhea
cytotec.misoprostol |
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