#Twinning
Percent of twins that are dizygotic
What is 70%?
TTTS results from this imbalance in placental vasculature.
What are arteriovenous (AV) anastomoses?
This sign suggests dichorionicity and is best seen at 11–14 weeks.
What is the lambda sign?
The most common complication associated with twins
What is preterm birth?
The first recorded case of conjoined twins appeared in this country in the 10th century.
What is Armenia?
Most common form of monozygotic twins
What is MCDA?
This staging system is used to grade TTTS severity.
What is the Quintero staging system?
A “T sign” seen on ultrasound during the first trimester suggests this type of twin pregnancy.
What is a monochorionic diamniotic (MCDA) pregnancy?
Vaginal progesterone is potentially helpful in this subset of twin pregnancies.
What is twins with short cervix (<25 mm)?
This country currently has the highest natural twin birth rate.
What is Benin (West Africa)?
DCDA twin delivery is recommended between these gestational weeks.
What is 37–38 weeks?
Intervention is considered in TRAP if this AC ratio is exceeded.
What is ≥50% acardiac-to-pump twin abdominal circumference ratio?
In MC twins, this Doppler is used to assess for TAPS starting at 16 weeks.
What is the middle cerebral artery peak systolic velocity (MCA PSV)?
The majority of twins are delivered between these gestational ages
What is 32 and 36+6 weeks?
The Minnesota Twin Study famously studied twins raised apart to answer this age-old debate
What is nature vs. nurture?
The phenomenon in which twins have different fathers
What is heteropaternal superfecundation?
The standard treatment for TTTS diagnosed before 28 weeks.
What is fetoscopic laser ablation?
Differential placental echogenicity and “starry sky” liver in one twin point to this diagnosis.
What is twin anemia-polycythemia sequence (TAPS)?
Cervical length below this threshold may prompt consideration for cerclage in twins.
What is ≤15 mm?
The only human twins raised by a she-wolf.
Who are Romulus and Remus
The usually quoted base exponent for Hellin's law describing twin frequency
What is 89?
Common transient ultrasound finding seen in donor twin after laser surgery for TTTS
What is hydrops?
This abnormality is seen in the donor twin’s bladder in stage II TTTS.
What is an absent or non-visible bladder?
The length at which contractions would make delivery within a week nearly 100% likely.
What is ≤30 mm?
The youngest self-made millionaires twin brand
Who were Mary-Kate and Ashley Olsen?