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