Multiple gestation Flashcards
What is multiple gestation?
The presence of more than one fetus in uterus at the same time.
What is the commonest variety of multiple pregnancy?
Twins
Describe the different ways of classifying multiple gestation(4)
Number of fetuses (twins, triplets, quadriplets)
Number of fertilized eggs: Zygosity
Number of placentae: Chorionicity
Number of amniotic cavities: Amnionicity
In terms of zygosity, describe the two types ,the type of twin seen and state which of the 2 is common.
Dizygotic twins (70 – 80%), resulting from fertilization of two ova leading to fraternal twin.
Monozyogotic twins (20 – 30%), %), resulting from fertilization of one ovum followed by splitting of developing zygote leading to identical twin
Describe the different types of monozygotic twins and state how often their occur(in terms of percentages)
Depending on time of division
Dichorionic diamniotic 25-30% (DCDA)
Monochorionic diamniotic 70-75% (MCDA)
Monochorionic monoamniotic 1-2% (MCMA)
Conjoined twins Very rare
SOMETHING TO NOTE
Not all dichorionic pregnancies are dizygotic
All monochorionic pregnancies are monozygotic.
Classify zygosity in terms of number of eggs, time of splitting ,number of placenta and number of sacs.
REFER TO HANDOUT
What is the relationship between the timing of splitting and the independency of the twins?
The earlier splitting of the single zygote occurs, the more independently the twins will develop.
What are the risk Factors of multiple gestation?(5)
1.Assisted reproductive techniques
-In vitro fertilisation
-Use of fertility medications
2.Maternal family history
3. Race
-High in African women
4.High parity (5 gravida onwards)
5.Increased maternal age (30 – 35 yrs)
How is multiple gestation diagnosed?
By taking a thorough history, doing a physical exam and ultrasonography.
What are the pertinent history taking points in someone with multiple gestation?
History of ovulation inducing drugs
Maternal family history of twins
Increase nausea and vomiting in early months
Palpitations or SOB
Leg swelling and/or hemorrhoids
Unusual rate of abdominal enlargement
What clinical exam findings can make you suspect multiple gestation(6)
Signs of anemia
Barrel shape abdomen
SF size/GA discrepancy
Palpation of too many fetal parts
Finding two fetal heads
Two distinct fetal heart sounds at separate spots with a silent area in between (of greater than 10bpm)
What are the findings on an ultrasonography?
T sign indicates an MC twin
A lambda sign -DC twin
Describe how you would diagnose the type of twin using ultrasound scan.
REFER TO HANDOUT
List 5 DDX of Multiple pregnancy.
Inaccurate menstrual history
Macrosomic baby
Polyhydramnios
Molar pregnancy
Fibroid in pregnancy
What are the maternal complications/risks associated with multiple gestation?(7)
1.Anemia
2.Abortion
3.Hyperemesis
4.Abruption
5.Hypertensive Disorders of pregnancy
6.Thromboembolism
7.PPH
In which classification is the risk FGR greatest and by how much?
DCDA twins risk 25% of SGA
MC twins risk of IUGR 50%
Describe the management of Fetal Growth Restriction.
Balance the risk of iatrogenic preterm delivery for a single growth restricted fetus.
Generally, avoid delivery before 28-30weeks
For MC twins, sIUFD may lead to death or severe handicap of the co-twin
Prefer delivery before IUFD of growth restricted twin
What is Twin to Twin transfusion Syndrome?
This is a syndrome in twin gestation that occurs when there is abnormal placental vascular anastomoses
There is A-V anastomoses but superficial anastomoses is lacking.
In which set of twins is TTS common?
MC twins
10% MCDA
5% MCMA
Describe the pathophysiology of twin to twin Transfusion Syndrome?
-There is A-v anastomoses but decreased or lacking of superficial a-a/v-v anastomoses as a result there is a donor twin giving blood to a receipient twin.
How does Polyhydramnios and Oligo come to be in TTS?
REFER TO NOTES
What is the criteria for the diagnosis of TTS?
Single placenta mass
Same gender
Oligohydramnios in one twin and polyhydramnios in the other
Discordant bladder appearences
Haemodynamic and cardiac compromise
What is the name of the grading system of TTS? Describe it
Quintero Severity grading for TTS.
Describe the Quintero Severity grading for TTS?
Stage 1-Poly/oligo hydramnios sequence
Stage 2- Bladder of donor twin not visible
Stage 3- Abnormal Dopplers are seen.
Stage 4-Hydrops in one or both fetus
stage5-Death of both or one fetus.
What are the treatment options of TTS?(6)
Expectant
Amnioreduction
Septostomy
Selective feticide
Laser ablation of anastomoses
Preterm delivery (above 28weeks)
At what stage is Laser ablation of anastomoses done?
Definitive Rx for TTTS stage 2 and above
Describe the management of multiple gestation during antepartum?
-Order USS scan for dating and chorionicity as early as possible
-Order a fetal anomaly scan between 18-22 weeks
-After 28 weeks ,order a a USS ever 2-3weeks for growth and do dopplers if discordant growth noted and if more than 2o% discordant growth then send to a central hospital.
- Ensure that ANC visits go as follows: Monthly up to 28weeks,every 2 weeks up to 36weeks then weekly up until delivery at 38weeks.
-Encourage them to eat more than 600kcla compared to a non-pregnant woman as well as a balanced diet.
-Delivery should be planned for around 38weeks
-if mono-mono refer to central hospital, give steroids at 28 weeks gestation, admit for monitoring using a CTG then plan for delivery around 32-34weeks via C/S
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What is the intrapartum management of Multiple gestation?
-Partograph to monitor labor progress
-Continuous fetal heart monitoring (CTG, Moyo)
Prepare two delivery sets and two neonatal resuscitation trolleys ready.
Assistants are needed
Prophylatic oxytocin IV
For cephalic presentation of the first twin and no compli cations,vaginal delivery no later than 39 weeks, plan for c/s delivery of earlier delivery is indicated.
-For delay greater than 30mins(retained twin), assess the lie and presentation and proceed accordingly.
1.For transverse lie of second twin,perform internal podalic version then breech extraction in OT
2. For cephalic presentation, start oxytocin augmentation.
- After delivery of secong twin,perfORM AMTSL followed by oxytocin 20IU/IL of NS IV at 30dpm
What are the indications for C/S in Multiple gestation?(7)
Caesarean section is indicated if:
If breech or transverse
Cord prolapse of the leading twin
Previous caesarean section
Triplets (or higher order pregnancy)
Intrauterine growth restriction
MC twins
Twin with complications: IUGR, conjoint twins
