What are discordant twins?
Twin growth discordance is a term used in obstetric imaging to describe a significant size or weight difference between the two fetuses of a twin pregnancy. To be classified as a growth discordance, some consider that the estimated fetal weight (EFW) of the smaller twin should fall under the 10th centile.
How is discordant twins diagnosed?
Antenatal ultrasound During later stages size discordance is better assessed using the abdominal circumference (AC) 2,3 and the disparity of 20 mm or more are usually taken as a cut-off value for considering the pregnancy as discordant.
What causes twin discordance?
The causes of twin growth discordance are often unknown. The most important is considered to be monochorionicity, mainly because of unequal sharing, or of velamentous cord insertions in the IUGR twin [20]. Other possible causes are “intrauterine crowding” and the presence of malformations [21-23].
What does discordant mean in pregnancy?
Birth weight discordance was defined as a difference of 20% or more of the weight of the heavier twin, associated with an intra-uterine growth restriction (10(th) percentile) of at least one twin. Ultrasound discordance was defined as a difference of estimated fetal weight>20%.
What is normal twin discordance?
About 75% of twins exhibit < 15% discordance (concordant), 20% are 15-25% (mildly) discordant, and about 5% are more than 25% (severely) discordant. Higher frequencies and increased severity are seen among triplets.
What is a discordance?
Definition of discordance 1 : lack of agreement or harmony : the state or an instance of being discordant. 2 music : dissonance.
How is discordance calculated?
Birth weight discordance =(larger twin weight−smaller twin weight) / larger twin weight×100.
What are the 5 varieties of twins?
Unique identical twins
- Mirror twins. Mirror twins are exactly what they sound like!
- Conjoined twins. Conjoined twins are a rare twin type in which the two siblings are physically connected.
- Parasitic twins.
- Semi-identical twins.
- Female and male identical twins.
What are the 7 different types of twins?
These different types of twins include:
- Identical Twins. Identical twins are one of the most common types of twins.
- Fraternal Twins. Also referred to as non-identical twins, fraternal twins are also quite common.
- Conjoined Twins.
- Parasitic Twins.
- Monozygotic Twins.
- Mirror-image Twins.
- Semi-identical Twins.
- Polar Body Twins.
What is the normal EFW in pregnancy?
Fetal biometry measures were 124.9 (11.4) mm for abdominal circumference, 41.4 (2.3) mm for biparietal diameter, and 26.9 (2.0) mm for femur length. EFW at 16–20 weeks adjusted for gestational age was 234 (30) grams and birth weight adjusted for gestational age was 3518 (420) grams.
How do you use discordance?
How to use discordance in a sentence
- The mountain rarely gives unity of country; far more frequently, duality, discordance, actual diversity.
- But a further difficulty arises from the discordance of the results of different experiments.
When you hear the term discordant twins, this means that the twins at birth show a distinct difference in size. Usually, the other twin’s weight is greater than 10%.
What is discordant phenotypic mosaicism in twins?
An unusual combination of findings in a monochorionic twin pregnancy (such as discordant sex, fetal size, or cystic hygroma in a single twin) may represent discordant phenotypic mosaicism; amniocentesis of both twins should be considered for diagnosis. 56, 63
Is discordant growth after fetal viability an indication for surveillance of twins?
Although there are limited data on the false-negative rate for twins who undergo antenatal tests,103 discordant growth after fetal viability is an indication for surveillance. Preterm delivery for discordance alone should not be undertaken.
What is Twin growth discordance and how is it treated?
Twin Growth Discordance may happen in 25% of twin pregnancies. This condition is associated with a number of things like IUGR (intrauterine growth restriction) in the smaller twin, TTTS (twin-to-twin transfusion syndrome), or having a single umbilical artery (SUA) which is the absence of the right or left umbilical artery.