What is the incidence of multiple pregnancies in developed countries over the last two decades?

Increased by 50%.

Which type of twins has a higher perinatal mortality rate, monochorionic (MC) or dichorionic (DC)?

Monochorionic (MC) twins.

What is the twinning rate in Nigeria compared to Japan?

54/1000 in Nigeria and 4/1000 in Japan.

What is the primary cause of cerebral palsy in multiple pregnancies?

Prematurity, intrauterine growth restriction (IUGR), and monochorionic twin complications.

What is the rate of dizygous twins compared to monozygous twins?

Two-thirds are dizygous, one-third are monozygous.

Which ultrasound feature indicates dichorionicity in twins?

A thick chorion septum.

What percentage of twins are monochorionic?

20%.

How does zygosity affect the risk of congenital heart disease in twins?

Monozygous twins have twice the risk of congenital heart disease compared to dizygous twins.

What is the common management strategy for twin pregnancies to minimize risks?

Single consultant-led team management focusing on fetal risk based on chorionicity.

Which procedure is preferred in DC twins for prenatal diagnosis?

Chorionic villus sampling (CVS) with separate sampling.

What is the perinatal mortality rate for triplets compared to singletons?

6 times higher in triplets.

What complication arises from placental vascular anastomoses in monochorionic twins?

Unbalanced blood flow leading to various complications.

Which diagnostic method is used to determine chorionicity with high accuracy in the first trimester?

Examination of dividing membrane layers.

What is the primary risk factor for gestational diabetes in multiple pregnancies?

Increased maternal physiological demands.

What is the twin–twin transfusion syndrome (TTTS) associated with?

Chronic blood shunting from donor to recipient twin.

What is the frequency of neurological issues in survivors of untreated TTTS?

Higher risk of neurological issues and cerebral palsy.

What is the typical delivery time for twins compared to triplets?

Twins at 37 weeks, triplets at 34 weeks.

What is the recommended management for high-order multiples to reduce risks?

Multifetal pregnancy reduction (MFPR).

What is the risk of miscarriage after amniocentesis in twin pregnancies?

Higher than in singleton pregnancies.

What percentage of conceptions may start as twins, leading to early pregnancy loss?

12%.

In the context of twin pregnancies, what does a 'twin peak' sign indicate?

Dichorionic twins.

What percentage of twins have a higher risk of structural anomalies due to zygosity?

MZ twins have a 50% higher risk.

How does chorionicity influence the management of anomalies in twins?

Zygosity determines abnormality risk, while chorionicity affects management options.

What is the consequence of one twin dying in a monochorionic twin pregnancy?

25% chance of ischemic lesions in the surviving twin.

What is the treatment for Twin Reversed Arterial Perfusion Sequence (TRAP)?

Amnioreduction, sulindac, or cord occlusion.

What is the primary challenge in delivering monoamniotic twins?

Cord entanglement.

What maternal physiological change is increased in multiple pregnancies?

Cardiac output.

How is the growth discordancy in twins calculated?

100 * [(EFW_larger − EFW_smaller) / EFW_larger].

What is the risk associated with a cervical length of <25 mm="" at="" 20–24="">

Increases preterm delivery risk from 19% to 48%.

What is the recommended practice for cesarean delivery rates in twin pregnancies?

Elective cesareans are preferred if the emergency rate exceeds 33%.